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adjective tan·gent \ˈtan-jənt\

Definition of tangent

  1. 1a :  meeting a curve or surface in a single point if a sufficiently small interval is considered <straight line tangent to a curve>b (1) :  having a common tangent line at a point <tangent curves> (2) :  having a common tangent plane at a point <tangent surfaces>

  2. 2 :  diverging from an original purpose or course :  irrelevant <tangent remarks>

Origin and Etymology of tangent

Latin tangent-, tangens, present participle of tangere to touch; perhaps akin to Old English thaccian to touch gently, stroke

First Known Use: 1594

Other Mathematics and Statistics Terms



noun tan·gent

Simple Definition of tangent

  • geometry : a line that touches a sphere or circle at only one point

Source: Merriam-Webster's Learner's Dictionary

Full Definition of tangent

  1. 1a :  the trigonometric function that for an acute angle is the ratio between the leg opposite to the angle when it is considered part of a right triangle and the leg adjacentb :  a trigonometric function that is equal to the sine divided by the cosine for all real numbers θ for which the cosine is not equal to zero and is exactly equal to the tangent of an angle of measure θ in radians

  2. 2 :  a line that is tangent; specifically :  a straight line that is the limiting position of a secant of a curve through a fixed point and a variable point on the curve as the variable point approaches the fixed point

  3. 3 :  an abrupt change of course :  digression <the speaker went off on a tangent>

  4. 4 :  a small upright flat-ended metal pin at the inner end of a clavichord key that strikes the string to produce the tone

Examples of tangent in a sentence

  1. <in the middle of her description of her dog's symptoms, she went off on a tangent about its cute behavior>

Origin and Etymology of tangent

New Latin tangent-, tangens, from linea tangens tangent line

First Known Use: 1594

Other Mathematics and Statistics Terms

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different from the usual or normal

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