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mathcore

n. (context music English) A rhythmically complex and dissonant style of metalcore music.

Wikipedia
Mathcore

Mathcore is a rhythmically complex and dissonant style of metalcore. It was pioneered by bands such as Converge, Coalesce, Botch, The Dillinger Escape Plan, and Candiria. The term mathcore is suggested by analogy with math rock. Both math rock and mathcore make use of unusual time signatures. Math rock groups such as Slint, Don Caballero, Shellac, Drive Like Jehu and Dazzling Killmen have some influence on mathcore, though mathcore is more closely related to metalcore. Prominent mathcore groups have been associated with grindcore.