foreskin

Short definition from Wiktionary

Noun

1. 1
   The nerve-dense, retractable fold of skin which covers and protects the head of the penis in humans and some other mammals.
2. 2
   Ellipsis of clitoral foreskin.

Verb

1. 1
   To remove the foreskin.
2. 2
   To sexually stimulate by manipulating the foreskin.