the original form of rock-'n'-roll, basically dependent on a consistently loud and strong beat. Cf. soft rock.
Pronunciation: (härd'rok"), [key]
(loosely) of or pertaining to igneous or metamorphic rocks, as in mining (hard'-rock min'ing) and geology (hard'-rock geol'ogy). Cf. soft-rock geology.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.