1. A worthless lazy fellow.
2. Large somewhat primitive fish-eating diving bird of the northern hemisphere having webbed feet placed far back; related to the grebes; SYN. diver.
Any of various birds of the genus Gavia, family Gavidae, found in N regions of the N hemisphere. Loons are specialized for swimming and diving. Their legs are set so far back that walking is almost impossible, and they come to land only to nest, but loons are powerful swimmers and good flyers.
They have straight bills and long bodies and feed on fish, crustaceans, and some water plants. There are just five species, the largest, the yellow-billed loon G. adamsii, being an Arctic species 75 cm/2.5 ft long.