Knaves, noun plural of knave. Synonyms in the same form.
Rascal
rascals, scoundrels, rogues, villains, miscreants, scamps, wretches, ruffians, bastards, swindlers, shysters, mischief-makers, mischiefs, cheats, rapscallions, hoodlums, hooligans, varlets, scapegraces, blackguards, scallywags, picaroons
Other
jacks, boys
All synonyms for knave →