Simple Definition of LSD

from our Learner's Dictionary

LSD

noun

ˌɛlˌɛsˈdiː How to pronounce LSD (audio)
: an illegal drug that causes people to see and hear things that do not really exist

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“LSD.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/LSD. Accessed 15 Apr. 2026.

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