From The Collaborative International Dictionary of English v.0.48 :
Elephantidae \Elephantidae\ n.
a natural family of mammals comrising the elephants.
Syn: family Elephantidae.
[WordNet 1.5]
From WordNet (r) 3.0 (2006) :
Elephantidae
n 1: elephants [syn: Elephantidae, family Elephantidae]