sit-upons🔊noun1plural of sit-upon2UK, Obsolete, Slang Trousers.But I should advise you, old fellow, to get your sit-upons seated with wash-leather,—just like the eleventh hussars do with their cherry-coloured pants.1860, Cuthbert Bede, The Adventures of Mr. Verdant Green, volumes 1-3, page 89: