Take the biscuit

This is the British sibling of the more international "take the cake," and like its cousin, it likely descends from the ancient Greek custom of awarding a cake as a prize for endurance or wit, an image that resurfaced in various European languages over the centuries. Why English speakers in Britain specifically shifted from "cake" to "biscuit" isn't documented anywhere; it may simply reflect that biscuits were the more everyday teatime item in British households. The phrase is recorded in British use from the late 19th century, without any surviving explanation of the swap.