Green’s Dictionary of Slang

crow’s nest n.2

[naut. use crow’s nest, the platform secured high on a mast that houses a lookout]

1. (UK society) a small bedroom on the higher floors of country houses, reserved for the use of bachelor guests.

[UK]J. Ware Passing Eng. of the Victorian Era 100/1: Crow’s nest (Soc.) Small bedroom for bachelors high up in country houses, and on a level with the treetops.

2. (US) the upper balcony or ‘gods’ in a theatre.

[US] in DARE.

3. (US gay) a club frequented by older homosexual men.

[US]B. Rodgers Queens’ Vernacular 25: a drinking establishment where the gay oldtimers meet [...] crow’s nest.