Green’s Dictionary of Slang

academy n.

[joc. uses of SE]

1. [late 16C–19C] a brothel, one of a number of contemporary terms based on brothel = school.

2. [early 18C] a casino.

3. [mid-18C] a lunatic asylum.

4. [late 18C–1950s] a prison; used in combs. such as Adkins’s academy n.; Campbell’s academy n.; floating academy n.

5. [mid-late 19C] a training ‘school’ for pickpockets.

6. [late 19C–1900s] a billiard room.