- a group or set of four persons or things.
- Bookbinding. four gathered sheets folded in two for binding together.
- an expression of the form a + bi + cj + dk, where a, b, c, and d are real numbers; i2 = j2 = k2 = −1; and ij = −ji = k, jk = −kj = i, and ki = −ik = j.
- a quantity or operator expressed as the sum of a real number and three complex numbers, equivalent to the quotient of two vectors. The field of quaternions is not commutative under multiplication.
Origin of quaternion
1350–1400; Middle English quaternioun < Late Latin quaterniōn- (stem of quaterniō), equivalent to Latin quatern(ī) four at a time + -iōn- -ion
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for quaternion
Even then the captain of the gate was replying to a question from the quaternion.Ulric the Jarl
William O. Stoddard
Should neither player be able to form a quaternion, then the game is drawn.
The quaternion was a gathering of four sheets of vellum, each folded once; thus forming sixteen pages.Illuminated Manuscripts in Classical and Mediaeval Times
J. Henry Middleton
William Hare, the second of our quaternion, was also a native of Ireland, having been born in the neighbourhood of Londonderry.The Court of Cacus
As regard class of the first quaternion, like Sancho Panza I have no intention of indicating how old these may be.Legends & Romances of Spain
- maths a generalized complex number consisting of four components, x = x 0 + x 1 i + x 2 j + x 3 k, where x, x 0 … x 3 are real numbers and i² = j² = k² = –1, ij = –ji = k, etc
- another word for quaternary (def. 5)
C14: from Late Latin quaterniōn, from Latin quaternī four at a time
- Any number of the form a + bi + cj + dk where a, b, c, and d are real numbers, ij = k, i2 = j2 = -1, and ij = -ji. Under addition and multiplication, quaternions have all the properties of a field, except that multiplication is not commutative.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.