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acid-head

American  
[as-id-hed] / ˈæs ɪdˌhɛd /
Or acidhead

noun

Slang.

  1. a person who habitually takes the drug LSD.

Etymology

Origin of acid-head

First recorded in 1965–70

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.