Green’s Dictionary of Slang

hold up v.1

[the demand that victims should hold up their hands]

1. [mid-19C+] to commit an armed robbery.

2. [late 19C–1950s] to cheat, to blackmail.

3. [late 19C–1960s] (US) to demand, esp. to charge an exorbitant price.

SE in slang uses

In phrases

hold up one’s clothes/dress at (v.)

[20C+] (W.I.) of a woman, to raise her skirts and expose her buttocks as a gesture of derision.