hummingbird hummingbird /ˈhʌm.ɪŋ.bɜːd/ aep /-bɝːd/ noun [C] ► F0 a very small brightly coloured bird with a long, thin beak, whose wings move very fast and make a humming noiseThesaurus+: ↑Other wild birds , ↑Birds which live by or on inland water , ↑Birds of prey