grebe
any aquatic bird, such as Podiceps cristatus (great crested grebe), of the order Podicipediformes, similar to the divers but with lobate rather than webbed toes and a vestigial tail
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
grebe
[grēb] (vertebrate zoology)
The common name for members of the family Podicipedidae; these birds have legs set far posteriorly, compressed bladelike tarsi, individually broadened and lobed toes, and a rudimentary tail.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.