| Noun | 1. | Colymbiformes - grebes order Colymbiformes, order Podicipediformes, order Podicipitiformes, Podicipediformes, Podicipitiformes animal order - the order of animals Aves, class Aves - (ornithology) the class of birds podicipitiform seabird - aquatic birds related to the loons family Podicipedidae, Podicipedidae - coextensive with the order Podicipitiformes |