any of numerous species of large noisy chiefly Australasian parrots with a crests and brightly coloured plumage: family Cacatuidae, esp genus Kakatoe
Aus, NZ, informal a small farmer
Aus, informal a lookout
[Dutch kaketoe from Malay kakatua, from kakak elder sibling + tua old; (sense 3) from the belief that a flock of cockatoos post a sentry while feeding]