Definition of tangent
(Entry 1 of 2)
1
: an abrupt change of course : digression
the speaker went off on a tangent
2a
: 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 adjacent
b
: 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
3
: 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
4
: a small upright flatended metal pin at the inner end of a clavichord key that strikes the string to produce the tone
tangent
adjectiveDefinition of tangent (Entry 2 of 2)
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
: diverging from an original purpose or course : irrelevant
tangent remarks
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MerriamWebster unabridged
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Time Traveler for tangent
The first known use of tangent was in 1594
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