Effete is an adjective describing something as feminine or effeminate. An alternative definition is for something to lack effectiveness, to not have strength or bravery or to be unable to act.
Its derivatives include effetely and effeteness.
Realise vs. realize
Than vs. then
Practice vs. practise
Learned vs. learnt
Adviser vs. advisor
Affect vs. effect
Its vs. it’s
Canceled vs. cancelled
Alumna, alumnae, alumni, alumnus
Center vs. centre
Fish vs. fishes
Favorite vs. favourite
Gray vs. grey