cock-a-hoopadv.

cock-a-hoopcock-a-hoop: [16] Cock-a-hoop comes from a 16th- and 17th-century expression set the cock on the hoop ‘make merry’ – but exactly how the expression arose is not clear. One obvious interpretation is that it meant ‘put the tap on the barrel’ – that is, let the wine or beer flow freely – but it has also been suggested that hoop here means ‘measure of grain’ (a sense which originated in the 16th century), the notion being that to put a cockerel on a heap of grain implied prodigality.