Synonyms for Differential (same or very similar meaning)
WordNet sense 1 (the result of mathematical differentiation; the instantaneous change of one quantity relative to another; df(x)/dx):
derivative, derived function, differential coefficient, first derivative
WordNet sense 2 (a bevel gear that permits rotation of two shafts at different speeds; used on the rear axle of automobiles to allow wheels to rotate at different speeds on curves):
differential gear
From the ODE community, based on WordNet
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