# secant

[see-kant, -kuh nt]

- Geometry. an intersecting line, especially one intersecting a curve at two or more points.
- Trigonometry.
- (in a right triangle) the ratio of the hypotenuse to the side adjacent to a given angle.
- (originally) a line from the center of a circle through one extremity of an arc to the tangent from the other extremity.
- the ratio of the length of this line to that of the radius of the circle; the reciprocal of the cosine of a given angle or arc. Abbreviation: sec

- cutting or intersecting, as one line or surface in relation to another.

## Origin of secant^{}

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

## Examples from the Web for secant

### Historical Examples

#### The complement of the logarithm of a sine, tangent, or secant.

The Sailor's Word-BookWilliam Henry Smyth

#### Secant equals one over cosine—um-m-m-m—one point oh three five.

Skylark ThreeEdward Elmer Smith

#### Every ray through S1 or S2 which is not a secant determines one of them.

#### That which is made by a right line, whether tangent or secant, with the circumference of a circle.

The Sailor's Word-BookWilliam Henry Smyth

#### The oblongs made of any secant from the same point, and of the outter segment of the secant are equall betweene themselves.

The Way To GeometryPeter Ramus

# secant

- (of an angle) a trigonometric function that in a right-angled triangle is the ratio of the length of the hypotenuse to that of the adjacent side; the reciprocal of cosineAbbreviation: sec
- a line that intersects a curve

## Word Origin

C16: from Latin secāre to cut

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

## Word Origin and History for secant

### n.

1590s, from Latin secantem (nominative secans) "a cutting," present participle of secare "to cut" (see section (n.)). First used by Danish mathematician Thomas Fincke in "Geometria Rotundi" (1583).

Online Etymology Dictionary, © 2010 Douglas Harper

# secant

[sē′kănt′]

- A straight line or ray that intersects a curve, especially a circle, at two or more points.
- The ratio of the length of the hypotenuse in a right triangle to the side adjacent to an acute angle. The secant is the inverse of the cosine.
- The reciprocal of the abscissa of the endpoint of an arc of a unit circle centered at the origin of a Cartesian coordinate system, the arc being of length x and measured counterclockwise from the point (1, 0) if x is positive or clockwise if x is negative.
- A function of a number x, equal to the secant of an angle whose measure in radians is equal to x.

The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.