n. 乳齿象

[ noun ]
extinct elephant-like mammal that flourished worldwide from Miocene through Pleistocene times; differ from mammoths in the form of the molar teeth
<noun.animal>

Mastodon \Mas"to*don\, n. [Gr. masto`s the breast + 'odoy`s,
'odo`ntos, a tooth. So called from the conical projections
upon its molar teeth.] (Paleon.)
An extinct genus of mammals closely allied to the elephant,
but having less complex molar teeth, and often a pair of
lower, as well as upper, tusks, which are incisor teeth. The
species were mostly larger than elephants, and their remains
occur in nearly all parts of the world in deposits ranging
from Miocene to late Quaternary time.