amtrac

or am·track

[am-trak]

Origin of amtrac

First recorded in 1940–45; am(phibious) + trac(tor)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Word Origin and History for amtrac
n.

amphibious assault vehicle, 1944, from amphibious + tractor.

Online Etymology Dictionary, © 2010 Douglas Harper