From Longman Dictionary of Contemporary Englishknee breechesˈknee ˌbreeches noun [plural] DCCtight trousers that end at your knee, worn especially in the past
Examples from the Corpus
knee breeches• Alfred was waving a white-stockinged leg in the air, Heinrich experimentally bending over in his black knee breeches.• Some still wore knee breeches, but tightly-fitting pantaloons buttoned round the ankle over the white silk socks were permitted. 