differential

Fetched 2026-10-26 (cache).

Synonyms: differentia, differentiae, deferential, differentiate, inferential, differentials, codifferential

Antonyms: differentia, differentiae, deferential, differentiate, inferential, differentials, codifferential

Related words from Datamuse; suggestions, not definitions.

Adjective

1. Of or pertaining to a [[difference]].
2. [[dependent|Dependent]] on, or [[making]] a difference; [[distinctive]].
3. Having differences in [[speed]] or [[direction]] of [[motion]].
4. {{lb|en|mathematics}} Of or pertaining to [[differentiation]] or the [[differential calculus]].

Noun

1. The [[differential gear]] in an [[automobile]], etc.
2. A [[qualitative]] or [[quantitative]] difference between [[similar]] or [[comparable]] things.
3. One of two [[coil]]s of [[conduct]]ing [[wire]] so related to one another or to a [[magnet]] or [[armature]] common to both, that one coil produces [[polar]] action contrary to that of the other.
4. A form of [[conductor]] used for dividing and distributing the [[current]] to a series of electric lamps so as to maintain equal action in all.<ref>{{R:Knight AMD}}</ref>
5. {{lb|en|calculus}} A quantity representing an [[infinitesimal]] change in a [[variable]], now only used as a [[heuristic]] aid except in [[nonstandard analysis]] but considered rigorous until the 20th century; a [[fluxion]] in {{w|Method of Fluxions|Newtonian calculus}}, now usually written in {{w|Leibniz's notation}} as <math>\operatorname{d}\!x</math>.
6. {{lb|en|calculus|of a [[univariate]] [[differentiable]] [[function]] <math>f(x)</math>}} A function giving the change in the [[linear]] [[approximation]] of <math>f</math> at a point <math>x</math> over a small interval <math>\Delta x</math> or <math>\operatorname{d}\!x</math>, the function being called the '''differential''' of <math>f</math> and denoted <math>\operatorname{d}\!f(x,\Delta x)</math>, <math>\operatorname{d}\!f(x)</math>, or simply <math>\operatorname{d}\!f</math>.
7. {{lb|en|{{w|multivariable calculus}}}} The [[Jacobian]] [[matrix]] of a function of several variables.
8. {{lb|en|differential geometry|of a [[smooth]] [[map]] <math>\phi</math> between [[smooth manifold]]s}} The [[pushforward]] or [[total derivative]] of <math>\phi</math>: a linear map from the [[tangent space]] at a point <math>x</math> in <math>\phi</math>'s domain to the tangent space at <math>\phi(x)</math> which is, in a technical sense, the best linear approximation of <math>\phi</math> at <math>x</math>; denoted <math>\operatorname{d}\!\phi_x</math>.
9. {{lb|en|mathematics}} Any of several [[generalize|generalizations]] of the concept(s) above: e.g. the {{w|Kähler differential}} in the setting of [[scheme]]s, the {{w|quadratic differential}} in the theory of [[Riemann surfaces]], etc.

Source: Wiktionary · CC BY-SA 4.0 (Wiktionary dump) · cached copy, not a rewrite.