Geom. Also 7 -gone, 8 -deka-. [irreg. f. L. quindecim, after decagon, dodecagon: see -GON. So F. quindécagone.] A plane figure having fifteen angles.
1570. Billingsley, Euclid, IV. xvi. 124. In a circle geuen to describe a quindecagon or figure of fiftene angles.
1651. T. Rudd, Euclide, 179. In a given Circle to inscribe a Quindecagon.
a. 1696. Scarburgh, Euclid (1705), 174. The Quindecagon is the only derivative Polygon that Euclide thought necessary to be consider’d.
1778. Learning at a Loss, II. 88. A Fellow … who … crams you with Pentagons, Hexagons and Quindekagons.
1886. Nixon, Euclid Revised, IV. xvi. 202. A regular … quindecagon can be circumscribed about a circle.
