early 15c., conformyte, conformite, "similarity, correspondence in form or manner," from Old French conformité (14c.), from Late Latin conformitatem (nominative conformitas), from conformis "similar in shape," from conformare "to fashion, to form, to shape; educate; modify," from assimilated form of com "together" (see con-) + formare "to form" (see form (v.)). Meaning "action in accordance with some standard" is from late 15c.; that of "adherence to the Church of England" is from 1620s. Modern spelling is from 17c.