Synonyms of diametric

2 Syllables
agin, polar, counter, flip-side, facing
3 Syllables
adverse, contrasting, contrary, converse, conflicting, reverse, flipside, wrongheaded
4 Syllables
unalike, antonymic, diametrical, antonymous, antithetic, unsimilar, antipodal, violative, antipodean, opposite
5 Syllables
antithetical, contradictory