versin
contracted f. versed sine (versed a.).
| 1827 Airy in Encycl. Metrop. (1845) I. 685 Versin c = 1 - cos c. Ibid., Versin c = versin a - b [etc.]. 1859 Parkinson Optics (1866) 254 The quantity of light received by the disc is 2π2a2B versin α. |
versin
contracted f. versed sine (versed a.).
| 1827 Airy in Encycl. Metrop. (1845) I. 685 Versin c = 1 - cos c. Ibid., Versin c = versin a - b [etc.]. 1859 Parkinson Optics (1866) 254 The quantity of light received by the disc is 2π2a2B versin α. |
Oxford English Dictionary