LSD

noun

ˌel-(ˌ)es-ˈdē 

: a semisynthetic illicit organic compound C₂₀H₂₅N₃O derived from ergot that induces extreme sensory distortions, altered perceptions of reality, and intense emotional states, that may also produce delusions or paranoia, and that may sometimes cause panic reactions in response to the effects experienced

called also lysergic acid diethylamide

Examples of LSD in a Sentence

Recent Examples on the Web

The exceptionally vivid colors that were a hallmark of their designs led some to wonder whether the Kroffts were influenced by the use of LSD, but Marty Krofft repeatedly denied such speculation. —Carmel Dagan, Variety, 13 Apr. 2026

Blotter paper can absorb fentanyl and other narcotics like LSD, which can then be distributed through the mail. —CBS News, 26 Mar. 2026

Users say taking small doses of psilocybin or LSD does everything from bolster productivity and creativity to ease symptoms of anxiety and insomnia — all without the hallucinogenic effects characteristic of a full-blown trip. —Tiney Ricciardi, Denver Post, 18 Mar. 2026

Bulger blamed his sleeping issues on his participation in a LSD project while incarcerated in the Federal prison system. —Boston Herald Editorial Staff, Boston Herald, 18 Mar. 2026

Word History

Etymology

borrowed from German, from Lysergsäure-Diäthylamid "lysergic acid diethylamide"

First Known Use

1950, in the meaning defined above

Kids Definition

LSD

noun

ˌel-ˌes-ˈdē 

: an illegal drug that causes abnormal sensations, extreme and changeable states of emotion, unnatural changes in the way time and space are experienced, and hallucinations and that may sometimes cause panic in response to the effects experienced

Medical Definition

LSD

noun

ˌel-ˌes-ˈdē 

: a semisynthetic illicit organic compound C₂₀H₂₅N₃O derived from ergot that induces extreme sensory distortions, altered perceptions of reality, and intense emotional states, that may also produce delusions or paranoia, and that may sometimes cause panic reactions in response to the effects experienced

called also acid, lysergic acid diethylamide, lysergide