(zoology) A univalve shell whose volutions run in the opposite direction to that of a standard screw thread. / (computing) An interactive command shell initiated from a remote computer.

Any of multiple bivalves, particularly a bean clam, but sometimes also a tellin or close relative.

(glaciology, oceanography) Ice which is no longer supported by the water beneath it, and instead has a cavity underneath.

A census-designated place in Contra Costa County, California, United States.

Lutraria lutraria, a large marine bivalve mollusc.

A shell company.

plural of shell corporation

Any clam of the family Mactridae.

Alternative form of seashell

Any mollusc of the genus Limatula.