▪ I. trisect, a. Bot. rare.
(ˈtraɪsɛkt)
[f. tri- + L. sect-us cut, as in palmatisect, pinnatisect.]
Of a leaf: Divided into three lobes quite to the base, but not articulated so as to form separate leaflets.
| 1899 Heinig Gloss. Bot. Terms, Sect, completely divided from margin to midrib into distinct parts, in comp. as trisect. |
▪ II. trisect, v.
(traɪˈsɛkt)
[f. tri- + L. sect-, ppl. stem of secāre to cut, after bisect.]
trans. To divide into three equal parts (esp. in Geom.); sometimes gen. to divide into three parts.
| 1695 W. Alingham Geom. Epit. 44 Trisect any side..in the points d and e. a 1696 Scarburgh Euclid (1705) 88 From hence 'tis manifest, how to trisect a Right angle. 1786 Phil. Trans. LXXVI. 16 Mr. Graham..perceived.. how very much more easy a given line was to bisect than to trisect or quinquesect. 1822 De Quincey Confess. 146 Could not I have reduced it a drop a day, or by adding water, have bisected or trisected a drop? 1876 A. J. Evans Through Bosnia ii. 48 We found the dwelling-houses trisected into a sleeping-room, a kitchen, and a store-room. |
Hence triˈsected ppl. a. (in Bot. = trisect a.); triˈsecting vbl. n.
| 1694 Phil. Trans. XVIII. 70 So the halving, trisecting, quartering, &c. is performed by extracting the Square Root, the Cubick, Biquadratick Roots, &c. of the Terms. 1809 Cavendish ibid. XCIX. 227 In trisecting, the greatest error we are liable to does not exceed that of bisection in a greater proportion than that of 4 to 3. 1828 Webster, Trisected, divided into three equal parts. 1866 Treas. Bot. 1174 Trisected, cut deeply into three parts. |