toff: [19] Toff probably originated as an alteration of tuft [14], which was used from the 18th century as an Oxford University slang term for a ‘titled undergraduate’ (students who came from noble families wore a gold tassel or ‘tuft’ on their caps). Tuft itself was adapted from Old French tofe or toffe ‘tuft’, a word of Germanic origin. => tuft[toff etymology, toff origin, 英语词源]
lower-class London slang for "stylish dresser, man of the smart set," 1851, said by OED to be probably an alteration of tuft, formerly an Oxford University term for a nobleman or gentleman-commoner (1755), in reference to the gold ornamental tassel worn on the caps of undergraduates at Oxford and Cambridge whose fathers were peers with votes in the House of Lords.