noun
A mechanical device that allows the outer drive wheel to rotate faster than the inner one during a turn, commonly used in automobiles.
自動車の差動歯車は、カーブで左右の車輪の回転差を吸収する。
A car's differential gear absorbs the difference in rotation between the left and right wheels when cornering.
Abbreviation of ディファレンシャルギア, a common colloquial term for the same device. 差動歯車 is the formal Japanese term.
Compound of 差動 (differential motion) and 歯車 (gear). A straightforward technical term with no obscure historical derivation.