1 persecutor, intimidator, tyrant:
That bully Roderick is always beating up the younger boys.
2 persecute, intimidate, tyrannize, torment, browbeat, daunt, awe, cow, terrorize; hector, harass, push around:
Roderick even bullied his best friend into parting with his allowance.
3 Old-fashioned jolly, worthy, admirable:
Ah, there you are, my bully boy!
4 Usually, Bully for (someone)! Bravo!, Great!, Fantastic!, Fabulous!, Marvellous!, Spectacular!; So what?, What of it?; US Peachy!, Dandy!, Neat-oh!; Old-fashioned Fantabulous!:
'David's won the snooker competition again.' 'Bully for him!'