alley cat

Short definition from Wiktionary

Noun

1. 1
   An urban feral cat.
2. 2
   A sexually promiscuous person, especially a woman.
3. 3
   A sexually promiscuous person, especially a woman: A (female) prostitute.
4. 4
   An informal bicycle race with checkpoints.

Verb

1. 1
   Synonym of cat around (“engage in sex with various partners”).