tangent, n. [L. tangens, -entis, p. pr. of tangere to touch; akin to Gr. having seized: cf. F. tangente. Cf. Attain, Contaminate, Contingent, Entire, Tact, Taste, Tax, v. t.].

A tangent line curve, or surface; specifically, that portion of the straight line tangent to a curve that is between the point of tangency and a given line, the given line being, for example, the axis of abscissas, or a radius of a circle produced. See Trigonometrical function, under Function. [1913 Webster]

Artificial tangent, or Logarithmic tangent, the logarithm of the natural tangent of an arc. -- Natural tangent, a decimal expressing the length of the tangent of an arc, the radius being reckoned unity. -- Tangent galvanometer (Elec.), a form of galvanometer having a circular coil and a short needle, in which the tangent of the angle of deflection of the needle is proportional to the strength of the current. -- Tangent of an angle, the natural tangent of the arc subtending or measuring the angle. -- Tangent of an arc, a right line, as ta, touching the arc of a circle at one extremity a, and terminated by a line ct, passing from the center through the other extremity o.

tangent, a. [L. tangens, -entis, p. pr.].

Touching; touching at a single point [1913 Webster]

Tangent plane (Geom.), a plane which touches a surface in a point or line. -- Tangent scale (Gun.), a kind of breech sight for a cannon. -- Tangent screw (Mach.), an endless screw; a worm.

top

OXFORD DICTIONARY

tangent, n. & adj.
--n.
1 a straight line, curve, or surface that meets another curve or curved surface at a point, but if extended does not intersect it at that point.
2 the ratio of the sides opposite and adjacent to an angle in a right-angled triangle.
--adj.
1 (of a line or surface) that is a tangent.
2 touching.

Idiom

at a tangent diverging from a previous course of action or thought etc. (go off at a tangent). tangent galvanometer a galvanometer with a coil through which the current to be measured is passed, its strength being proportional to the tangent of the angle of deflection.

Derivative

tangency n.

Etymology

L tangere tangent- touch

top

THESAURUS

tangent

abutter, adjoiner, air line, approach, asymptote, axis, beeline, borderer, bottleneck, bystander, chord, collision course, concentralization, concentration, concourse, concurrence, confluence, conflux, congress, convergence, converging, crossing, diagonal, diameter, direct line, directrix, edge, focalization, focus, funnel, great-circle course, hub, immediate neighbor, looker-on, meeting, mutual approach, narrowing gap, neighbor, neighborer, normal, onlooker, perpendicular, radius, radius vector, right line, secant, segment, shortcut, side, spokes, straight, straight course, straight line, straight stretch, straightaway, streamline, transversal, vector

top

ROGET THESAURUS

tangent

Contiguity

N contiguity, contact, proximity, apposition, abuttal, juxtaposition, abutment, osculation, meeting, appulse, rencontre, rencounter, syzygy, coincidence, coexistence, adhesion, touching, (touch), borderland, frontier, tangent, abutter, contiguous, touching, in contact, conterminous, end to end, osculatory, pertingent, tangential, hand to hand, close to, with no interval.

For further exploring for "tangent" in Webster Dictionary Online