polytomy
(pəˈlɪtəmɪ)
[f. Gr. πολυ-, poly- + -τοµια, f. -τοµος cut. Cf. F. polytomie.]
The condition or character of being polytomous. (Distinguished from dichotomy and trichotomy.)
1. Bot. Division into several (more than two) branches at the same point.
| 1875 Bennett & Dyer Sachs' Bot. 148 Dichotomy (rarely Polytomy)..is caused by the cessation of the previous increase in length of a member at the apex, and by two (or more) new apices arising at the apical surface close to one another, which..develope in diverging directions. |
2. Logic. Division into several (usually, more than three) members.
| a 1856 W. Hamilton Lect. Metaphysics & Logic (1860) IV. xxv. 23 If a division has only two members, it is called a dichotomy..; if three, a trichotomy..; if four, a tetrachotomy; if many, a polytomy, &c. 1864 Bowen Logic iv. 101 Division into many members may be called a polytomy. 1867 Atwater Logic 71 A division in three members is called a Trichotomy: into many members, a Polytomy. |