1. gavialgavi*al , n. [hind. ghariu l: cf. f. gavial.] (zo?l.) a large asiatic crocodilian (gavialis gangeticus); -- called also nako, and gangetic crocodile.note: the gavial has a long, slender muzzle, teeth of nearly uniform size, and feet completely webbed. it inhabits the ganges and other rivers of india. the name is also applied to several allied fossil species