bit of stuff n.
1. [mid-18C+] (also drop of stuff, lump of stuff, piece of stuff) a young woman, usu. attractive and often out enjoying herself.
2. [early 19C] a prize-fighter.
3. [early 19C] an overdressed man; an over-confident man.
4. [mid-19C] (also bit) an admirable person.
5. [late 19C–1900s] (Aus.) a horse.
6. [1900s-40s] (Aus./Irish) a tough, aggressive young man.
[late 19C+] to have sexual intercourse.