Green’s Dictionary of Slang

oof n.

also offtish, ooftish
[Ger. auf tische, on the table. The term originated c.1850 and, according to the Sporting Times ‘the aristocracy of Houndsditch, being in the habit of refusing to play cards, unless the money were “on the table”’; thus Grey, Hoods (1952): ‘Tauchess offen tisch, boyus. What’s my cut?’]

[late 19C–1930s] money.

In derivatives

oofless (adj.)

[late 19C-1910s] impoverished.

oofy (adj.) [note Wodehouse’s wealthy character Oofy Prosser (lit. ‘Rich Scrounger’]

[late 19C–1920s] rich, wealthy.

In compounds

oof-bird (n.) (also oof-bag)

[late 19C–1910s] a source of money, one who can supply money.

In phrases

pad the oof (v.)

[1900s] (Aus. Und.) to present a roll of banknotes folded in such a way that each one is counted twice.