Until the cows come home
People can talk, wait, or engage in virtually any number of pastimes until the cows come home, which means a very long but indefinite time. The expression dates in this sense from the early 1600s. The first citation generally given is from a play called The Scornful Lady written by Francis Beaumont and John Fletcher in 1616, where it appears as ‘kiss till the cow come home’. The expression derives from the languid behaviour of cows who are never in a hurry. When cows have been out to pasture, they will return home in their own sweet time.