Why is it called acid jazz?

The music played by a generation raised on jazz as well as funk and hip-hop, Acid Jazz used elements of all three. Its existence as a percussion-heavy, primarily live music placed it closer to jazz and Afro-Cuban than any other dance style, but its insistence on keeping the groove allied it with funk, hip-hop, and dance music. The term itself first appeared in 1988 as both a record label and the title of a compilation series that reissued jazz-funk music from the '70s -- often called "rare groove" during a major mid-'80s resurgence. A variety of acid jazz artists emerged during the late '80s and early '90s, including either primarily live bands such as Stereo MC's, James Taylor Quartet, the Brand New Heavies, Groove Collective, Galliano, and Jamiroquai or studio projects like Palm Skin Productions, Mondo Grosso, Outside, and United Future Organization.

the term 'acid jazz' was coined by a radio DJ mashing up an old jazzy song with an acid house music beat. and also because this type of music was associated with acts signed to the Acid Jazz record label

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Because it only sounds like jazz if you are on acid. Otherwise you recognize it for what it is: the rnb equivalent of the Grateful Dead

ACID JAZZ MUSICIANS LIKE COKE BUT WHEN PUSHED WILL use acid. Stan Getz prefered acid to any other form of mind altering substances.