cash on the nail

cash on the nail

Payment that is made immediately, on the spot, or without delay. Primarily heard in UK. I could put the bill on my credit card, but if it's all right with you, I'd rather we divvy it up between us and pay now, cash on the nail. After a few bad experiences with lodgers, I've learned to demand cash on the nail for the rent every Sunday, no exceptions.
See also: cash, nail, on