psychedelic drug vs hallucinogenic drug

psychedelic drug and hallucinogenic drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
psychedelic drug	Yes	No	No	No
hallucinogenic drug	Yes	No	No	No

As nouns, psychedelic drug and hallucinogenic drug are synonyms defined as:

psychedelic drug and hallucinogenic drug: a psychoactive drug that induces hallucinations or altered sensory experiences

Other synonyms of psychedelic drug include hallucinogen, psychodelic drug.

psychedelic drug (noun)	hallucinogenic drug (noun)
a psychoactive drug that induces hallucinations or altered sensory experiences	a psychoactive drug that induces hallucinations or altered sensory experiences