talk the hind leg off a donkey talk incessantly. British informal

☞ In 1808 talking a horse's hind leg off was described as an 'old vulgar hyperbole' in Cobbett's Weekly Political Register, but the version with donkey was current by the mid 19th century. In 1879 Anthony Trollope mentioned talk the hind legs off a dog as an Australian variant.

1970Nina BawdenThe Birds on the Trees Talk, talk-talk the hind leg off a donkey, that one.