- loon - a worthless lazy fellow
--1 is a kind of idler, loafer, do-nothing, layabout, bum
- loon, diver - large somewhat primitive fish-eating diving bird of the northern hemisphere having webbed feet placed far back; related to the grebes
--2 is a kind of gaviiform seabird
--2 is a member of Gavia, genus Gavia- addle-head, addlehead, loon, birdbrain - a person with confused ideas; incapable of serious thought
--3 is a kind of misfit
- loon, diver - large somewhat primitive fish-eating diving bird of the northern hemisphere having webbed feet placed far back; related to the grebes