coversed sine

plural coversed sines

1. mathematicsThe trigonometric function 1 − sin(x).

   For the coversed sine; subtract the sine of the angle from 1. Thus, for the same angle we have the coversed sine, 1 — ·36650 = ·6335.

   1838, William Grier, The Mechanic′s Pocket Dictionary, page 21

   3 more examples

   The cosine of an arc is the sine of its complement.† In like manner, the coversed sine, cotangent, and cosecant of an arc, are respectively the versed sine, tangent, and secant of its complement.

   1825, Jas Thomson, Elements of Plane and Spherical Trigonometry, page 2

   At the top of the page on the left-hand side is placed the number of degrees, and in the left-hand column each minute of the degree, opposite to which are arranged the numerical values of the sine, coversed sine, &c, of the corresponding angle in those columns, at the top of which those terms are placed.

   1830, W. Hopkins, “Book II: Elements of Trigonometry”, in Geometry, Plane, Solid, and Spherical, page 46

   Hence the cosines and versed sines of zenith distances are respectively equal to the sines and coversed sines of the corresponding angular elevations.

   1871, Homersham Cox, The Law and Science of Ancient Lights, 2nd edition, page 109

   Synonyms: coversine, coversin