blue cheer noun a type of LSD (usually mixed with Methedrine) supplied in blue pills or capsules US From Blue Cheer, a branded detergent.
In the package, 250 caps of Blue Cheer, so I thought I would give a party. — Richard Neville, PlayPower, p. 240, 1970
Blue Cheer [formed in 1966] appeared in the summer of 1968 [...] the group was named for an especially high-quality strain of LSD. — TheRollingStoneEncyclopaediaofRock&Roll, p. 52, 1983