Английский разговорный словарь (основной) - wack adjective (youth culture)

In young people's slang (especially in the US): bad, unhip, harmful. Etymology: Possibly derived from wacky or wacko 'crazy, mad' (the former in slang use since the turn of the century, the latter a variant of the late seventies and eighties and apparently a favourite with New York mayor Ed Koch). The connection with drugs can be seen in wacky tabacky, a slang name for the drug of the sixties, marijuana. The implication is both that drugs affect the mind, and (in the case of the present use) that it is mad to get involved with them. History and Usage: Wack seems to have arisen in the street slang of US cities in the second half of the eighties, especially in connection with the spread of crack. It has been used in writing especially in the anti-drug slogan crack is wack (or crack be wack, jack) notably in a number of mural paintings in New York and other cities. Another inscription...warned, 'Crack is wack. You use crack today, tomorrow you be bumming. That's word experience talk.' Atlantic Sept. 1989, p. 75 Blacks and Jews have a lot more in common than most American ethnic groups...Cultured Americans...know a bad that's good from a bad that's bad. So who's perfect already? Fly maybe, dope maybe, def maybe, and down by law, but perfect--oy gevalt! What wack, farmished, loc-ed-out dreck. Interview Mar. 1990, p. 148