The state of being sharply different

divergence, incompatibility, disparity, variation, variance, dissimilarity, inequality, distinction, incongruousness, heterogeneity, oppositeness, contradiction, dissimilitude, diversity, unlikeness, disagreement, opposition; see also difference 1.

Antonyms agreement*, similarity*, uniformity. *

A contrasting effect

contrariety, antithesis, contradiction, inconsistency, foil, reverse, contraposition, inverse, adverse, converse, opposition; see also difference 2, opposite.

Antonyms equality*, unity*, oneness*, sameness.

To provide a contrast

contradict, disagree, conflict, set off, be contrary to, diverge, depart from, deviate from, differ from, mismatch, vary, show difference, stand out, be dissimilar, be diverse, be variable, be unlike, be a foil to; see also differ 1, oppose 1.

Antonyms agree*, concur*, be identical.

To indicate a contrast

oppose, differentiate, set over, set off against; see compare 2, distinguish 1. See syn. study at compare.