From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): ( n.) A sea god in the service of Neptune who assumed different shapes at will. Hence, one who easily changes his appearance or principles.

(2): ( n.) A genus of aquatic eel-shaped amphibians found in caves in Austria. They have permanent external gills as well as lungs. The eyes are small and the legs are weak.

(3): ( n.) A changeable protozoan; an amoeba.

The Nuttall Encyclopedia [2]

In the Greek mythology a divinity of the sea endowed with the gift of prophecy, but from whom it was difficult to extort the secrets of fate, as he immediately changed his shape when any one attempted to force him, for it was only in his proper form he could enunciate these secrets.