Green’s Dictionary of Slang

bank n.1

1. [19C] the vagina, esp. when seen as a means of making money; one of a number of terms pointing up the commercial potential of the vagina; the man also ‘places a deposit in it’.

2. [mid-18C; 20C+] (Aus./US black/campus) money, one’s fortune.

3. [1900s–40s] (US black) the lavatory; esp. visit the bank, take a trip to the bank.

4. (US prison) a solitary confinement cell [the prisoner is secure as ‘money in the bank’].

In phrases

make bank (v.)

[1990s+] (US black) to make money.

SE in slang uses

In compounds

bank-bandit pills (n.) [their calming effect, suitable for use during a robbery]

[1960s+] (drugs) depressants.

bank-man (n.)

[1900s] (US Und.) a bank robber.

In phrases

bank of Dunlop (n.) [brandname Dunlop, manufacturer of rubber tyres]

[1990s+] a fig. ‘bank’ on which ‘rubber’ cheques are drawn.

bank off (v.) [similarity of the punishment block to a bank vault]

[1930s+] (US prison) to place an inmate in the punishment cells.

bank on (v.) [gambling jargon bet the bank, to commit oneself completely]

[late 19C+] to take for granted, to assume as a certainty.

right as a bank (adj.) (also right as the bank)

[1900s–50s] (N.Z.) perfectly satisfactory, perfectly happy.