Qua-tẽr'ni-on1, n.
n. [Lat. quaternio, from quaterni, four each, from quatuor, four; Fr. quaternion.]
- The number four. [Poet.] Milton.
- A set of four parts, objects, or individuals.
He put him in prison, and delivered him to four quaternions of soldiers to keep him. Acts xii. 4. Ye elements, the eldest birth Of Nature’s womb, that in quaternion run. Milton.
- A word of four syllables; a quadrisyllable. “The triads and quaternions with which he loaded his speech.” W. Scott.
- (Math.) The quotient of two vectors, or of two directed right lines in space, considered as depending on four geometrical elements, and as expressible by an algebraic symbol of quadrinomial form.
☞ The science or calculus of quaternions is a new mathematical method in which the conception of a quaternion is unfolded and symbolically expressed, and is applied to various classes of algebraical, geometrical, and physical questions, so as to discover theorems, and to arrive at the solution of problems. Sir Wm. R. Hamilton.