[adjective] not compatible; "incompatible personalities"; "incompatible colors"
[adjective] used especially of drugs or muscles that counteract or neutralize each other's effect Synonyms:antagonistic
[adjective] not suitable to your tastes or needs; "the uncongenial roommates were always fighting"; "the task was uncongenial to one sensitive to rebuffs" Synonyms:uncongenial
[adjective] incapable of being used with or connected to other devices or components without modification
[adjective] of words so related that one contrasts with the other; "`rich' and `hard-up' are contrastive terms" Synonyms:contrastive