Green’s Dictionary of Slang

peep n.1

1. [mid-18C–1930s] an eye; often in pl.

2. [1990s+] a look.

3. (Aus.) a peepshow.

In compounds

peep joint (n.) [joint n. (3b)]

[1960s] (US) a striptease club or place where women pose in booths covered by screens which can be opened for set periods by coin-in-the-slot payments.

In phrases

on the peep (adv.)

[1900s] (US) at a glance.

peeps dig the range (v.) [dig v.3 (5) + SE range]

[1930s–40s] (US black) to look around one’s immediate environs.

put the peep on (v.)

[1940s] (US) to run surveillance on.