var·i·ant / ˈve(ə)rēənt/ • n. a form or version of something that differs in some respect from other forms of the same thing or from a standard: clinically distinct variants of malaria | [as adj.] a variant spelling.

VARIANT. (1) Different in some aspects while the same or similar in others: a variant reading of a text; AmE color and BrE colour are variant spellings of the same word, each conforming to different national norms. (2) A similar but distinct form: the words despatch and dispatch are spelling variants, the first common in BrE, the second common in AmE; the Scots word warsle can be regarded as a variant of standard English wrestle.

variant.
1. Name for differing versions of same piece of mus.

2.   Sudden changes from major to minor.

3.   Differing versions of folk-songs, the tune often slightly altering from region to region.