1. [late 19C+] (orig. US black, also kat) a person; also as term of address.
2. (orig. US black) in orig. jazz-orientated uses .
(a) [1920s+] a jazz musician.
(b) [1920s+] a smartly dressed, fashion conscious man; thus sharp cat.
(c) [1930s] a jazz fan.
3. [1980s+] a user of crack cocaine.
[1950s] (orig. US black) fashionable clothing as favoured by jazz fans.
[1960s+] (US black) a strutting style of walking, intended to emphasize one’s pride, independence and masculinity.
[1940s] (US black) a lookout man.
[1940s] (US black) a playboy.
see dig v.3
[mid-19C] a person as needed in a given situation; usu. in negative.