Monkey

In finance, a Monkey is British slang for 500 pounds sterling. The term monkey came from soldiers returning from India, where the 500 rupee note had a picture of a monkey on it. They used the term monkey for 500 rupees and on returning to England the saying was converted for sterling to mean £500.

Just lost a monkey in poker.

Pound sterling

The pound sterling (symbol: £), commonly known as the pound and less commonly referred to as Sterling, is the official currency of the United Kingdom, Jersey, Guernsey, the Isle of Man, South Georgia and the South Sandwich Islands, the British Antarctic Territory, and Tristan da Cunha.

A sum of 20 millions pound sterling was voted as compensation to the planters.