2 entries under this word

Differential

Dĭf'fer-ĕn'tial, a.

adjective

a. [Fr. différentiel, It. differenziale, Sp. diferencial. See DIFFERENCE.]

  1. Creating a difference; discriminating; special; as differential duties. “For whom he procured differential favors.” Motley.
  2. (Math.) Pertaining to a differential, or to differentials.
  3. (Mech.) (a.) Differing in amount or in the producing force; — said of motions or effects. (b.) Intended to produce or indicate difference of motion or effect; — said of machinery, &c.

Differential calculus. See CALCULUS.—Differential co-efficient, the limit of the ratio of the increment of a function of a variable to the increment of the variable itself, when these increments are indefinitely small.—Differential coupling, a form of slip-coupling used in light machinery to regulate at pleasure the velocity of the connected shaft.—Differential gear, a combination of wheel-work by which a motion is produced equal to the difference between two other motions.—Differential motion, an adjustment by which a single combination is made to produce such a velocity-ratio as would by ordinary arrangements require a considerable train of mechanism.—Differential screw, a compound screw by which a motion is produced equal to the difference of the motions of the component screws.—Differential thermometer, a thermometer for measuring very small differences of temperature.

A differential thermometer with a long graduated tube connecting two bulbs.
Differential Thermometer.
A differential-motion mechanism with two cylinders and a pulley.
Differential Mo- tion. A, small cylinder; B, large cylinder; C, pulley.

Dĭf'fer-ĕn'tial, n.

noun

n. (Math.) An increment, usually an indefinitely small one, which is given to a variable quantity.

☞ According to the more modern writers upon the differential and integral calculus, if two or more quantities are dependent on each other, and subject to variations of value, their differentials are any other quantities whose ratios to each other are the limits to which the ratios of the variations approximate, as these variations are reduced nearer and nearer to zero.