/ Dictionary / Index A acid-head: Meaning and Definition of Find definitions for: ac•id-head Pronunciation: (as'id hed"), [key] — n. Slang. a person who habitually takes the drug LSD. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: acid-head (Thesaurus) acid-forming acid house Related Content Daily Word Quiz: resilient Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language