mas·to·don (măstə-dŏn′) also mas·to·dont (-dŏnt′)
Any of several very large, extinct proboscidian mammals of the family Mammutidae of the Miocene, Pliocene, and Pleistocene Epochs, resembling elephants but having molar teeth of a different structure.
[New Latin Mastodōn, genus name : Greek mastos, breast, nipple + Greek odōn, tooth (from the nipple-shaped protrusions on the crowns of its molars); see dent- in the Appendix of Indo-European roots.]
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