A
- A cappella
- A la (à la)
- A priori
- A whole nother
- Abandon vs. abandonment
- Abdicate, abnegate, abrogate
- Abetter vs. abettor
- Abided vs. abode
- Abjure vs. adjure
- Abolishment vs. abolition
- Aborted vs. abortive
- About-face
- Abstruse vs. obtuse
- Acclimate, acclimatise, acclimatize
- Accord vs. accordance
- Acknowledgement vs. acknowledgment
- Ad hoc
- Ad hominem (usage)
- Ad infinitum
- Ad nauseam
- Ad vs. add
- Adamance
- Adapter vs. adaptor
- Adaption vs. adaptation
- Addicting vs. addictive
- Addiction vs. dependence
- Addition vs. edition
- Admission vs. admittance
- Adopted vs. adoptive
- Advance vs. advanced
- Adverse vs. averse
- Advert vs. avert
- Advice vs. advise
- Adviser vs. advisor
- Aegis
- Aeon vs. eon
- Aeroplane vs. airplane
- Aesthetic vs. ascetic
- Affect vs. effect
- Affective vs. effective
- Afflict vs. inflict
- Afterward vs. afterwards
- Afterward vs. afterword
- Ageing vs. aging
- Aggravate
- Aggression vs. aggressiveness
- Agnostic vs. atheist
- Agree
- Ahold
- Aid vs. aide
- Ain't
- Aisle vs. isle
- Alas
- Albeit
- All but
- All that
- All-around, all-round
- Alligator vs. crocodile
- Allude vs. elude
- Allusion vs. elusion vs. illusion
- Alphabetic vs. alphabetical
- Altar vs. alter
- Alternate vs. alternative
- Although vs. though
- Aluminium vs. aluminum
- Amalgam vs. amalgamation
- Ambiance vs. ambience
- Amend vs. emend
- Amiable vs. amicable
- Amok vs. amuck
- Among vs. amongst
- Amoral vs. immoral
- Amount vs. number
- Ample
- Amuse vs. bemuse
- Analog vs. analogue
- Analogue vs. analogy
- Analyse vs. analyze
- Anathema
- Annex vs. annexe
- Anyplace
- Anytime vs. any time
- Anyway vs. anyways
- Ape vs. monkey
- Apologise vs. apologize
- Apotheosis
- Appal vs. appall
- Appraise vs. apprise
- Appropriate vs. expropriate
- Apropos
- Archaeology vs. archeology
- Argumentative vs. argumentive
- Armor vs. armour
- Around the clock, round the clock
- Around vs. round
- Arouse vs. rouse
- Arrant vs. errant
- Arse vs. ass
- Artefact vs. artifact
- Ascared
- Ascent vs. assent
- Ascent, ascendance, ascendancy, etc.
- Asphalt, cement, concrete, pavement
- Assail vs. assault
- Assent vs. consent
- Assume vs. presume
- Assure, ensure, insure
- Attache
- Attain vs. obtain
- Au contraire
- Auger vs. augur
- Aught
- Aural vs. oral
- Authorise vs. authorize
- Authoritative vs. authoritive
- Autumn vs. fall
- Avail
- Avant-garde
- Avocation vs. vocation
- Ax vs. axe
- Axel vs. axle
B
- Bad rap vs. bad wrap
- Bail vs. bale
- Bait vs. bate
- Bald-faced vs. boldface
- Balmy vs. barmy
- Baloney vs. bologna
- Ban vs. bar
- Band (together) vs. bandy (about)
- Bankster
- Bar mitzvah and bat mitzvah
- Barbed wire
- Bare vs. bear
- Bawl out
- Bazaar vs. bizarre
- Beckon call
- Beeline
- Beg the question (usage)
- Beggar belief
- Behavior vs. behaviour
- Belated
- Belie
- Bellwether
- Bereaved vs. bereft
- Berserk
- Betwixt
- Beyond the pale
- Biannual vs. biennial
- Big-ups
- Bight vs. bite
- Blaspheme
- Blatant vs. flagrant
- Blather vs. blither
- Blessed vs. blest
- Bloc vs. block
- Blond vs. blonde
- Bona fide, bona fides
- Bore, boor, boar
- Borne vs. born
- Borough, burro, burrow
- Botanic vs. botanical
- Boughten
- Bourgeois, bourgeoisie
- Bowdlerize
- Brainchild
- Breach, breech, broach
- Breastfeeding, breastfed, breastfeed, etc.
- Breath vs. breadth (vs. width)
- Breath vs. breathe
- Bridle vs. bridal
- Briton
- Broach vs. brooch
- Brouhaha
- Buck naked, butt naked
- Buffer vs. buffet
- Bulk, balk, baulk
- Bupkis
- Burgle vs. burglarize
- Burned vs. burnt
- Burthen
- But vs. yet
- By and by vs. by the by
- Bête noire
C
- C'est la vie
- Cacao vs. cocoa
- Cache vs. cachet
- Caddie vs. caddy
- Cahoots
- Caliber vs. calibre
- Callous vs. callus
- Calvary vs. cavalry
- Canard
- Canceled vs. cancelled
- Canon vs. cannon
- Canvas vs. canvass
- Capiche, capeesh, capische, etc
- Capital vs. capitol
- Careen vs. career
- Carrot, carat, karat, caret
- Carte blanche
- Casted
- Catalog vs. catalogue
- Catty-corner, kitty-corner
- Caveat
- Cede vs. concede
- Center vs. centre
- Centrifugal vs. centripetal
- Centrifuge vs. subterfuge
- Centuries
- Certainty vs. certitude
- Cession vs. session
- Chafe vs. chaff
- Chasten vs. chastise
- Check vs. cheque
- Checkout vs. check out
- Cherry-pick
- Chic vs. sheik
- Childish vs. childlike
- Chili vs. chilly
- Chink vs. kink
- Chopper vs. copter
- Classic vs. classical
- Clean vs. cleanse
- Clench vs. clinch
- Cliffs Notes
- Climactic vs. climatic
- Co-op vs. co-opt
- Coarse vs. course
- Coliseum vs. colosseum
- College vs. university
- Collegial vs. collegiate
- Color vs. colour
- Comic vs. comical
- Commentator vs. commenter
- Compel vs. impel
- Complacent vs. complaisant
- Complement vs. compliment
- Compose vs. comprise
- Concave vs. convex
- Conceive vs. perceive
- Concerted
- Condemn vs. condone
- Confidant vs. confidante
- Connexion
- Connote vs. denote
- Contemporaneous vs. contemporary
- Contemptible vs. contemptuous
- Continual vs. continuous
- Contumely
- Cooperate vs. co-operate
- Copyright vs. copywrite
- Coral vs. corral
- Cord vs. chord
- Cornet vs. coronet
- Corollary vs. correlation
- Cosmetology vs. cosmology
- Costed
- Cosy vs. cozy
- Could care less
- Council vs. counsel
- Counselor vs. counsellor
- Coup de grace
- Crap
- Crapshoot
- Crayfish, crawfish, crawdad, etc.
- Creeped vs. crept
- Crevasse vs. crevice
- Crick (variant of creek)
- Crumby vs. crummy
- Cue vs. queue
- Cum
- Curb vs. kerb
- Customise vs. customize
- Cutesy
D
- D'oh
- Dam vs. damn
- Daresay
- Data
- Day in age (day and age)
- De facto
- De rigueur
- Dead set, dead-set, deadset
- Dealt vs. dealed
- Dearth
- Decent vs. descent
- Deconstruction
- Decry vs. descry
- Deduce vs. induce
- Deep-seeded vs. deep-seated
- Defence vs. defense
- Defuse vs. diffuse
- Deign
- Demur vs. demure
- Denounce vs. renounce
- Dependant vs. dependent
- Depository vs. repository
- Deprecate vs. depreciate
- Descendant vs. descendent
- Destroy vs. destruct
- Detract vs. distract
- Device vs. devise
- Dialectal vs. dialectical
- Different from, different than, different to
- Dike vs. dyke
- Dilemma
- Disassemble vs. dissemble
- Disburse vs. disperse
- Disc vs. disk
- Discombobulate
- Discomfit vs. discomfort
- Discrete vs. discreet
- Disenfranchise vs. disfranchise
- Disillusion vs. dissolution
- Disinterested vs. uninterested
- Dispatch vs. despatch
- Dispense with vs. dispose of
- Disposed vs. predisposed
- Dissociate vs. disassociate
- Distinct vs. distinctive
- Distrust vs. mistrust
- Divers vs. diverse
- Divorcée, divorcé, divorcee
- Dog-eat-dog
- Dole out vs. doll out
- Doppelgänger
- Double entendre
- Double vs. redouble
- Doughnut vs. donut
- Douse vs. dowse
- Dove vs. dived
- Downfall vs. downside
- Draft vs. draught
- Dreamed vs. dreamt
- Dribble vs. drivel
- Drier vs. dryer
- Droll
- Du jour
- Dual vs. duel
- Duly noted
- Dwelled vs. dwelt
- Dyeing vs. dying
E
- E-book, ebook, eBook
- E-mail vs. email
- E. coli
- E.g. vs. i.e.
- Each other vs. one another
- Earthy vs. earthly
- Economic vs. economical
- Economics vs. finance
- Eek vs. eke
- Elder, eldest
- Electric, electrical, electronic
- Elegy vs. eulogy
- Elicit vs. illicit
- Emigrate vs. immigrate
- Eminent vs. immanent vs. imminent
- Empathetic vs. empathic
- Empathy vs. sympathy
- En route
- En vogue, in vogue
- Enclose vs. inclose
- Endear
- Endeavor vs. endeavour
- Endemic vs. epidemic
- Enervate
- Enervate vs. innervate
- Engrain vs. ingrain
- Enormity vs. enormousness
- Enquire vs. inquire
- Enrol vs. enroll
- Enthuse
- Entitled vs. titled
- Entomology vs. etymology
- Envelop vs. envelope
- Envision vs. envisage
- Envision vs. invision
- Envoi vs. envoy
- Epicenter
- Epigram vs. epigraph
- Eponymous
- Equable, equatable, equitable
- Equivalence vs. equivalency
- Ere vs. err
- Ergo
- Ersatz
- Especial
- Esprit de corps
- Estimate vs. estimation
- Et al.
- Et cetera (etc.)
- Ethics vs. morals
- Evacuate
- Evoke vs. invoke
- Ex post facto
- Exalt vs. exult
- Exercise vs. exorcise
- Exhibit vs. exhibition
- Existent vs. extant
- Existential
- Expectant vs. expecting
- Exploitative vs. exploitive
F
- Fabulist
- Facepalm
- Factoid
- Fain vs. feign
- Fair vs. fare
- Fait accompli
- Falsehood, falsity, falseness
- Fantods
- Far East, Middle East, Near East
- Farther vs. further
- Faun vs. fawn
- Faux
- Faux pas
- Favor vs. favour
- Favorite vs. favourite
- Fay, fey
- Faze vs. phase
- Fearful vs. fearsome
- Feminity vs. femininity
- Fervent vs. fervid
- Fiancé and fiancée
- Fiber vs. fibre
- Fictional vs. fictitious
- Figurehead
- Filet vs. fillet
- Financer vs. financier
- Firefight
- Firing line vs. line of fire
- First floor
- Firstly, secondly, thirdly, etc.
- Flack vs. flak
- Flair vs. flare
- Flammable vs. inflammable
- Flaunt vs. flout
- Flautist vs. flutist
- Flavor vs. flavour
- Flesh out vs. flush out
- Flied
- Flier vs. flyer
- Flora and fauna
- Flounder vs. founder
- Flu vs. flue
- Foolproof vs. full-proof
- For all intensive purposes (for all intents and purposes)
- Fora vs. forums
- Forbear vs. forebear
- Forbidding vs. foreboding
- Force majeure
- Forego vs. forgo
- Foreword vs. forward
- Forte
- Fortuitous vs. fortunate
- Foul vs. fowl
- Frankenstein's monster
- Fraught
- Free rein vs. free reign
- Fritter away
- Frivolity vs. frivolousness
- Fueled/fueling vs. fuelled/fuelling
- Fulfil vs. fulfill
- Full stop vs. period
- Full-fledged, fully fledged
- Fulsome
- Funereal
- Funner, funnest
- Furor vs. furore
G
- Gaff vs. gaffe
- Gainsay
- Galore
- Gambit
- Gantlet vs. gauntlet
- Gaol vs. jail
- Gargle vs. gurgle
- Gaudy vs. gawdy
- Gaveled vs. gavelled
- Gender vs. sex
- Gesundheit
- Gibe, jibe, jive
- Gild vs. guild
- Gimme
- Ginormous
- Glad-hand
- Glamour vs. glamor
- Glom onto
- Gobbledygook
- Gobsmacked
- Gofer vs. gopher
- Gonna
- Goodly
- Gorilla vs. guerrilla
- Got vs. gotten
- Governance vs. government
- Grammar vs. usage
- Grandfather (as a verb)
- Grateful vs. gratified
- Gray vs. grey
- Grill vs. grille
- Grinded
- Grisly vs. grizzly
- Ground zero
- Guesstimate
- Gung-ho
H
- Habeas corpus
- Hail vs. hale
- Hair's breadth (hare's breath)
- Half-mast vs. half-staff
- Hallow vs. hollow
- Halve
- Hangar vs. hanger
- Hanged vs. hung
- Happenstance
- Hara-kiri
- Harbor vs. harbour
- Hardy vs. hearty
- Hark, harken, and hearken
- Hash out, thrash out
- Hawk vs. hock
- Heal vs. heel (and bring to heel)
- Healthful vs. healthy
- Hear, hear vs. here, here
- Heighth
- Hence
- Heroin vs. heroine
- Heterogeneous vs. heterogenous
- Hew vs. hue
- Hie
- Highfalutin
- Historic vs. historical
- Histrionic, histrionics
- Hoard vs. horde
- Holey vs. holy
- Home in vs. hone in
- Homely vs. homey
- Homo sapiens
- Homogenous vs. homogeneous
- Hoosegow
- Hoover vs. vacuum
- Horsey, horsy, horsie
- Hosanna
- Hullabaloo
- Humongous
- Humor vs. humour
- Humus vs. hummus
- Hurdle vs. hurtle
I
- Ice tea vs. iced tea
- Idea vs. ideal
- Idle, idol, idyll
- Ilk
- Illegible vs. unreadable
- Immaculate Conception vs. virgin birth
- Immunity vs. impunity
- Impactful
- Impassable vs. impassible
- Impassive vs. passive
- Impending vs. pending
- Imperious vs. impervious
- Impinge vs. infringe
- Imply vs. infer
- Imposter vs. impostor
- Impugn vs. impute
- In kind
- In the throes of
- Inalienable vs. unalienable
- Incentivize, incent
- Incidence vs. incidents
- Incipient vs. insipient (vs. insipid)
- Incomparable vs. uncomparable
- Incredible vs. incredulous
- Inequality vs. inequity
- Inequity vs. iniquity
- Inexplicable vs. unexplainable
- Infect vs. infest
- Ingenious vs. ingenuous
- Insofar (in so far)
- Installation vs. installment
- Installment vs. instalment
- Instantly vs. instantaneously
- Instinctive vs. instinctual
- Intercourse
- Interment vs. internment
- Interpretative vs. interpretive
- Invaluable vs. valuable
- Invite (as a noun)
- Ipso facto
- Ironic
- Irregardless
- Iteration
J
- Jam vs. jamb
- Je ne sais quoi
- Jejune
- Jeremiad
- Jewelry vs. jewellery
- Judgment vs. judgement
- Judicial vs. judicious
- Junction vs. juncture
- Junkie vs. junky
- Jury-rig, jerry-rig, jerry-built
- Just deserts vs. just desserts
K
- Kafkaesque
- Kaput
- Ketchup, catsup, catchup
- Kibosh
- Kick off vs. kickoff (vs. kick-off)
- Klutz
- Kowtow
- Kudos
L
- Labeled vs. labelled
- Labor vs. labour
- Laissez-faire
- Lambast vs. lambaste
- Landlubber
- Lasagna vs. lasagne
- Laudable vs. laudatory
- Lay out vs. layout
- Lay vs. lie
- Lead vs. lede
- Leaped vs. leapt
- Learned vs. learnt
- Led vs. lead
- Lend vs. loan
- Lest
- Levee vs. levy
- Libel vs. slander
- Licence vs. license
- Licorice vs. liquorice
- Lieutenant
- Light vs. lite
- Lighted vs. lit
- Lightening vs. lightning
- Likable vs. likeable
- Linchpin vs. lynchpin
- Liter vs. litre
- Literally vs. figuratively
- Lo, lo and behold
- Loath vs. loathe (vs. loth)
- Lonely vs. lonesome
- Look out vs. lookout (vs. look-out)
- Lorry
- Luddite
- Lustful vs. lusty
- Luxuriant vs. luxurious
M
- Macintosh, mackintosh, McIntosh
- Maddening vs. madding
- Magnate vs. magnet
- Magnum opus
- Make do vs. make due
- Maleficent vs. malevolent
- Mancession
- Maneuver vs. manoeuvre
- Mantel vs. mantle
- Many vs. much
- Marinade vs. marinate
- Marry vs. merry
- Marshal vs. martial
- Masterful vs. masterly
- Materiel vs. material
- Math vs. maths
- Maul vs. mull
- Mayonnaise vs. mayonaise
- Mea culpa
- Meager vs. meagre
- Means
- Medal, meddle, metal, mettle
- Mediator vs. moderator
- Melted vs. molten
- Memento mori
- Mensch
- Meta
- Metaphoric vs. metaphorical
- Meteoroid, meteor, meteorite (and meteoric)
- Meter vs. metre
- Methinks
- Mic vs. mike
- Milieu
- Minuscule vs. miniscule
- Mirandize
- Misinformed vs. uninformed
- Misnomer
- Modeling vs. modelling
- Modern
- Modus operandi (m.o, MO)
- Mold vs. mould
- Mollusc vs. mollusk
- Mollycoddle
- Molt vs. moult
- Momentarily
- Money-grabbing vs. money-grubbing
- Moot vs. mute
- Morays vs. mores
- Moreso
- Mothball
- Movable vs. moveable
- Mowed vs. mown
- Muchly
- Mucous vs. mucus
- Multitask
- Must of (must've)
- Muumuu
N
- Nary a
- Naught vs. nought
- Nauseating vs. nauseous
- Naval vs. navel
- Neandertal vs. neanderthal
- Nebbish
- Neighbor vs. neighbour
- Newfangled
- Nimby, nimbyism
- Nimrod
- Non sequitur
- Nonplussed
- Nonprofit vs. not-for-profit (vs. non-profit)
- Normalcy vs. normality
- Not hardly
- Notwithstanding
- Nunchucks
O
- O vs. oh
- Object lesson
- Observance vs. observation
- Obsolescent vs. obsolete
- Ocher vs. ochre
- Odor vs. odour
- Offence vs. offense
- Oftentimes
- Oh well
- Omelet vs. omelette
- On the lam
- One and the same, one in the same
- One-time vs. onetime
- One-upmanship
- Onus
- Opossum vs. possum
- Oppress, repress, suppress
- Oral vs. verbal
- Ordinance vs. ordnance
- Organise vs. organize
- Orientate
- Ouster
- Overdo vs. overdue
- Overtones vs. undertones
- Oxymoron
P
- Paean, paeon, peon
- Pair vs. pare vs. pear
- Pajamas vs. pyjamas
- Palate, palette, pallet
- Pale in comparison
- Pall vs. pallor
- Par excellence
- Paralyse vs. paralyze
- Paramount vs. tantamount
- Parlay vs. parley
- Parricide vs. patricide
- Passed vs. past
- Patsy
- Peace of mind, piece of (one's) mind
- Peak vs. peek vs. pique
- Peal vs. peel
- Pedal vs. peddle vs. petal
- Pell-mell
- Penal vs. penile
- Pendant vs. pendent
- Per diem
- Per se
- Percent vs. per cent
- Perchance
- Periodic vs. periodical
- Pernickety vs. persnickety
- Perquisite vs. prerequisite (vs. requisite)
- Persecute vs. prosecute
- Persona non grata
- Perspective vs. prospective
- Peruse
- Petrifaction vs. petrification
- Phial vs. vial (vs. vile)
- Phony vs. phoney
- Picaresque vs. picturesque
- Pickup vs. pick up (vs. pick-up)
- Piecemeal
- Pincer vs. pincher
- Pixelated vs. pixilated
- Plain vs. plane
- Plainclothes
- Playwright vs. playwrite
- Plenitude vs. plentitude
- Plethora
- Plough vs. plow
- Plum vs. plumb
- Point of view, standpoint, viewpoint
- Polemic vs. polemical
- Politics
- Pollyanna
- Polygamy vs. polygyny vs. polyandry
- Pompom vs. pompon (vs. pom-pom etc.)
- Ponderous
- Poo vs. pooh
- Populace vs. populous
- Pore over vs. pour over
- Port vs. starboard
- Portend vs. portent
- Potentiality
- Practicable vs. practical
- Practice vs. practise
- Pray vs. prey
- Precede vs. proceed
- Premier vs. premiere
- Preposition vs. proposition
- Prescribe vs. proscribe
- Presumptive vs. presumptuous
- Pretence vs. pretense
- Preventative vs. preventive
- Principal vs. principle
- Problematic vs. problematical
- Procrastinate
- Prodigal son
- Program vs. programme
- Prophecy vs. prophesy
- Proportional vs. proportionate
- Props
- Prostate vs. prostrate
- Protagonist, antagonist
- Protégé
- Psych vs. psyche
- Psychiatry vs. psychology
- Purposely vs. purposefully
Q
- Qualitative vs. qualitive
- Qualitative, quantitative
- Quantitative vs. quantitive
- Quash vs. squash
- Quasi
- Quid pro quo
- Quisling
R
- Rack vs. wrack
- Racket vs. racquet
- Radical
- Raison d'etre
- Rappel vs. repel
- Rapt vs. wrapt
- Raring to
- Ravaging vs. ravishing
- Re-create vs. recreate
- Reactionary vs. reactive
- Realise vs. realize
- Reappropriate
- Recent vs. resent
- Recur vs. reoccur
- Regard vs. regards
- Regime vs. regimen
- Regrettable vs. regretful
- Relevance vs. relevancy
- Remunerate vs. renumerate
- Repel vs. repulse
- Resilience vs. resiliency
- Restaurateur vs. restauranteur
- Retch vs. wretch
- Review vs. revue
- Rife vs. ripe
- Riff vs. rift
- Riffraff
- Ring vs. wring
- Rogue vs. rouge
- Role vs. roll
- Root vs. route vs. rout
- Rubenesque
- Rumor vs. rumour
- Runaway vs. run away
- Résumé
S
- Saccharin vs. saccharine
- Sacrilege, sacrilegious
- Safe-deposit box
- Sang froid
- Sanitise vs sanitize
- Sans
- Savanna vs. savannah
- Savior vs. saviour
- Savoir faire
- Scarfs vs. scarves
- Sceptic vs. skeptic
- Schadenfreude
- Scot-free
- Scuttlebutt
- Sear vs. seer vs. sere
- Secede vs. succeed
- Secret vs. secretive
- Sensual vs. sensuous
- Sentient
- Service (as a verb)
- Set up vs. setup
- Sew vs. sow
- Shanghai (as a verb)
- Shaved vs. shaven
- Shear vs. sheer
- Sheath vs. sheathe
- Shelf vs. shelve
- Shell out
- Sherbert vs. sherbet
- Shoo-in
- Showrunner
- Shtick
- Sic
- Sic vs. sick
- Sight vs. site
- Silicon vs. silicone
- Simpatico
- Sine qua non
- Skilful vs. skillful
- Smack of
- Smelled vs. smelt
- Smite, smote, smitten
- Smorgasbord
- Sneaked vs. snuck
- Somber vs. sombre
- Someplace vs. some place
- Somersault
- Soup up
- Spatter vs. splatter
- Speciality vs. specialty
- Specter vs. spectre
- Spelled vs. spelt
- Spendthrift
- Spilled vs. spilt
- Spoiled vs. spoilt
- Spur vs. spurn
- Stained glass
- Stalactite, stalagmite
- Stanch vs. staunch
- Stank, stunk
- Star-crossed
- Stationary vs. stationery
- Status quo
- Statute of limitations
- Sticktoitiveness
- Stock, shares
- Storey vs. story
- Straight vs. strait
- Strait-laced
- Straitjacket
- Stratagem vs. strategy
- Subconscious vs. unconscious
- Substantial vs. substantive
- Subtle vs. subtil
- Suffice it to say
- Sui generis
- Sulfur vs. sulphur
- Summary vs. summery
- Supposed to
- Surveil
- Svengali
- Swath vs. swathe
- Sweat vs. sweated
- Systematic vs. systemic
T
- T-shirt, t-shirt, tee-shirt, tee shirt
- Tack vs. tact
- Tail vs. tale
- Take over vs. takeover
- Takeaway and takeout
- Teetotaler, teetotaller
- Telegram vs. telegraph
- Tenant vs. tenet
- Testament vs. testimony
- Tete-a-tete
- Than vs. then
- The Bronx
- The late
- Theater vs. theatre
- Their, there, they're
- Threw vs. through
- Tic vs. tick
- Tidbit vs. titbit
- Till, until, 'til
- Timber vs. timbre
- Tire vs. tyre
- To vs. too
- To wit
- Toilette
- Tolerance vs. toleration
- Ton vs. tonne
- Topography vs. typography
- Torturous vs. tortuous
- Totaled/totaling vs. totalled/totalling
- Tough row to hoe
- Tour de force
- Toward vs. towards
- Toxicology vs. toxology
- Translucent vs. transparent
- Transpire
- Transport vs. transportation
- Traveled/traveling vs. travelled/travelling
- Trawl vs. troll
- Treasurys
- Treble vs. triple
- Troop vs. troupe
- Trope
- Trustee vs. trusty
- Tunneled, tunneling vs. tunnelled, tunnelling
- Turbid, turgid, torpid
- Turtle, tortoise, terrapin
U
- Uber
- Unawares
- Underwater vs. under water
- Unique
- Unkempt, unkept
- Unputdownable
- Untoward
- Up to date
- Upmost vs. utmost
- Upshot
V
- Vacuous vs. vapid
- Vagina vs. vulva
- Vain, vein, and vane
- Vamoose
- Verbiage
- Verses vs. versus
- Vertex vs. vortex
- Vice versa
- Vice vs. vise
- Vicious vs. viscous
- Vis-a-vis
- Viz.
- Voicemail
- Voilà
- Vouchsafe
W
- Wack vs. whack
- Waddle vs. wattle
- Wagon vs. waggon
- Waist vs. waste
- Waive vs. wave
- Waiver vs. waver
- Wander vs. wonder
- Wane, wax
- Wanton vs. wonton
- Warrantee vs. warranty
- Wary vs. weary
- Web site vs. website
- Well-heeled
- Wet vs. whet
- Whac-A-Mole
- Whence vs. from whence
- Whereas
- While away vs. wile away
- Whilst
- Whiny, whiney, whinny, Whinney
- Whiskey vs. whisky
- Whiz, whizz, wiz
- Who vs. whom
- Who's vs. whose
- Whoever vs. whomever
- Whoop vs. whup
- Widow, widower
- Wilful vs. willful
- Winningest
- Wintery vs wintry
- Wit vs. whit
- Wither vs. whither
- Wonkish, wonky
- Wont
- Woolen vs. woollen
- Workout vs. work out
- Wreath vs. wreathe
- Wrong vs. wrongly
- Wunderkind
Y
- Y'all
- Yea, yeah, yay
- Yoghurt vs. yogurt
- Yoke vs. yolk
- Your vs. you're
Z
- Zee vs. zed
- Zeitgeist
