a discordant state; disagreement; discord.

an instance of this.

dissonance.

Geology . lack of parallelism between adjacent strata, as in an angular unconformity.

(in genetic studies) the degree of dissimilarity in a pair of twins with respect to the presence or absence of a disease or trait.

noun

clash , confrontation , contention , difference , difficulty , disaccord , discord , dissension , dissent , dissentience , dissidence , dissonance , faction , friction , inharmony , schism , strife , variance , war , warfare