Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Cosine" Definition
noun
In a right triangle, the ratio of the length of the side adjacent to an acute angle to the length of the hypotenuse.
Source: American Heritage Dictionary
The abscissa at 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.
Source: American Heritage Dictionary
A trigonometric function that for an acute angle is the ratio between the leg adjacent to the angle when it is considered part of a right triangle and the hypotenuse.
Source: Merriam-Webster
A trigonometric function cos θ that for all real numbers θ is given by the sum of the alternating series and that is exactly equal to the cosine of an angle of measure θ in radians.
Source: Merriam-Webster