Disc vs. disk

There is no consensus on the difference between disc and disk, and in many contexts the two are used interchangeably. Disk is the standard spelling for computer-related terms such as hard disk and floppy disk. Disc is the standard spelling for phonograph records, albums (in the figurative sense—a group of songs presented in sequence), and components of plows and brake systems. But both spellings are commonly used for (1) CDs, DVDs, and other compact optical disks; (2) flat, plate-like bones; (3) flat, circular objects, and (4) disk-shaped celestial bodies. There are trends: disc is more common than disk for CDs, DVDs, etc. and plate-like bones, and disk is more common for disk-shaped things in outer space. But these trends are not so pronounced as to be conclusive.


Disk is indisputably the correct spelling for computer storage drives—for example:

If you must use a disk, there’s software that lets you use the optical drive on another network-connected computer. [Boston Globe]

It’s packed with features, including disk quotas to make sure none of your employees guzzles too much disk space. [Telegraph]

And disc is preferred for music records, albums, and machine parts—for example:

As well as the gramophones, Mr Thorne’s collection includes phonographs and disc and cylinder recorders. [Daily Mail]

The disc was the first release under West’s new “long-term worldwide label agreement” for his imprint through Def Jam. [Los Angeles Times]

Braking is accomplished with four-wheel disc brakes, 11.4-inch ventilated discs in front and 12.1-inch in the rear. [Montreal Gazette]

Elsewhere, usage of disc and disk is chaotic, and there are no clear rules (and usage guides differ on the matter). Our guess is that disk will eventually supplant disc in all but the latter’s special uses, but we’ll have to wait and see.

26 thoughts on “Disc vs. disk”

  1. I’m a New Zealander and FYI my impression of this issue is this:
    “Disk” is, and I think has always been, the American spelling for any “discular” object – until recently I’ve never seen an American use “disc”. “Disc” is the English spelling for the same thing. When “floppy disk” and “hard disk” became more widely used, the dominance of America in the software and computer industry meant that people in all countries became used to seeing “floppy disk” not “floppy disc”, and worldwide most people who usually would use “disc” adopted that convention for computer-related usage, although I know some English computer companies (Amstrad at least) stubbornly stuck with “disc” – but I suspect even they have given it up now. The Compact Disc was so spelled on the logo, so even Americans started spelling it that way for CD (and DVD).
    So now I think “disc” is used for a CD or similar optical disc in any country, and in UK is the default spelling for any disc-like object, and “disk” is used for a computer disk (hard or floppy) in any country and in the USA is the default spelling for any disc-like object.
    I may be totally off here but that’s the impression I have got from my observations over the last few decades :-)

  2. Discus … Latin / Greek roots.  The British had a much more intimate inculcation of Latin and Greek spelling influences in the 1800s than survived the trip across The Pond.   American spelling patterns tend toward the rustic — dropping unvoiced word parts, simplifying word spelling, and “correction” of ambiguous c-pronounced-as-S / c-pronounced-as-k issues by changing to the K when helpful at breaking pronunciation logjams.

    German-speaking tribes (in a way curiously Germanic) just eliminated the whole dichotomy entirely.  If it is pronounced like a “K”, then it is spelled with a “K”.  No exceptions.  Ja.  Hence they took the Latin “Cæsar” and respelled it Kaiser.  The French though love their linguistic transcriptional ambiguities, so not only did they leave it Cæsar, but twisted the leading C from its original K pronunciation to an S pronunciation.

    The British, ever infatuated with the regal French affectations, went along hook, line and sinker.  Hence … why so damned many words have loss-of-cultural focus between consistent spelling and pronunciation.

    So sez me, an Anglophone American of passing machismo.

  3. For geeks, Disc refers to optical media and disk refers to magnetic media. For all others, a generic flat round item is a disc in the UK and disk in the USA.

  4. “Disc” (short for discus) refers to anything round, regardless of whether it is referencing a computer object (CD) or otherwise (frisbee is a flying disc or your spine has discs).

    • your definition of disc is the best here. it would also include data stored in a circular configuration. a record disc is not just round or plate-shaped, the data storage (the grooves) is organized in a circular configuration. also there’s the spinning nature of its operation to consider…

    • “Disk” also refers to anything round, regardless of whether it is referencing a computer object. At least, that’s the practice in the US. Neither spelling has special meaning in general use. The “Disk” spelling is the more common one in the US. If you want to sound smart you can claim that the “Disc” spelling comes from a Latin origin, whereas the “Disk” spelling comes from a Greek influence; although, that may have nothing to do with why it’s more commonly spelled “Disk” in the US.

  5. What if it refers to the act of discing? as in farming? discing gets the red underline and disking with a K does as well. It looks better with the C (to me). the tool used has several round metal discs that cut up the ground, i say it is discing, my friend doesn’t agree…

    • I prefer disk for all (it has Greek origins) specifically because of the agricultural references as I work in the farming sector. Normally a C before E or I is soft (as S)(except in words of Germanic origin) and discing the soil just looks wrong to me though disking doesn’t look right, I just force it!!

  6. I find it funny that I am replying using DISQus.
    In my opinion, disc is an older term, used in a most generic sense. However, disk refers to a type of storage in media, electronics, and computers. I say flat objects and not flat and circular objects because of the existence of “floppy disks”.

  7. I play ultimate, and we refer to frisbees as “discs” more often than as frisbees. I came here to see if they mention ultimate, but sadly, no. I’m taking a guess and saying that it’s “disc” and not “disk” because of the company called discraft that makes frisbees.

  8. Is “disc” really the common spelling when used for phonograph records (that is, Gramophone record)? The original spelling used in the patents is “disk”. You also see “disk” in older references. Philips and Sony used the spelling “disc” for CDs. This is the only correct spelling when used in context with CDs. The name of the invention, after all, is “Compact Disc”. When speaking of Gramophone records, the original spelling was “disk”, but it’s hard to say what is most used today. It all gets confused with CDs. I’m not sure what spelling vinyl record geeks would prefer we use today, but I would defer to their preference since they are the only ones likely to care these days.

  9. Came here looking for an answer … now I think I have even less certainty. Until a few minutes ago, I used ‘disc’ mainly, ‘disk’ occasionally … though now I’m blowed if I can say for sure what for! Must admit, I prefer the explanation that it’s ‘disk’ in the USA, and ‘disc’ in the UK, and everywhere else that we spell English words properly. :-)

  10. A disc has an optical medium (CD, DVD, Blue Ray), while a disk has a magnetic medium (Hard Drive, Floppy Disk, VHS, Cassette Tapes).This may not mean much to the average person, but to someone in IT, well it’s on our Comptia A+ exam normally.


Leave a Comment