Giants of mighty bone and bold emprise. Milton.

Giant's Causeway, a vast collection of basaltic pillars, in the county of Antrim on the northern coast of Ireland.

Giant cell. (Anat.) See Myeloplax. -- Giant clam (Zoöl.), a bivalve shell of the genus Tridacna, esp. T. gigas, which sometimes weighs 500 pounds. The shells are sometimes used in churches to contain holy water. -- Giant heron (Zoöl.), a very large African heron (Ardeomega goliath). It is the largest heron known. -- Giant kettle, a pothole of very large dimensions, as found in Norway in connection with glaciers. See Pothole. -- Giant powder. See Nitroglycerin. -- Giant puffball (Bot.), a fungus (Lycoperdon giganteum), edible when young, and when dried used for stanching wounds. -- Giant salamander (Zoöl.), a very large aquatic salamander (Megalobatrachus maximus), found in Japan. It is the largest of living Amphibia, becoming a yard long. -- Giant squid (Zoöl.), one of several species of very large squids, belonging to Architeuthis and allied genera. Some are over forty feet long.