From BiblePortal Wikipedia

Webster's Dictionary [1]

(a.) Pertaining to the elephant, or resembling an elephant (commonly, in size); hence, huge; immense; heavy; as, of elephantine proportions; an elephantine step or tread.

The Nuttall Encyclopedia [2]

A small island below the first cataract of the Nile; contains interesting monuments and ruins of the ancient Roman and Egyptian civilisations.