Define hardcore. hardcore synonyms, hardcore pronunciation, hardcore translation, English dictionary definition of hardcore. adj. also hard-core 1. Intensely loyal; die-hard: a hardcore secessionist; a hardcore golfer.

History: The Agile Manifesto. On February 11-13, 2001, at The Lodge at Snowbird ski resort in the Wasatch mountains of Utah, seventeen people met to talk, ski, relax, and try to find common ground—and of course, to eat.