Meaning of QUATERNION in English

QUATERNION

kwəˈtərnēən, -wäˈt- noun

( -s )

Etymology: Middle English quaternioun, from Late Latin quaternion-, quaternio, from Latin quaterni four each (from quater four times) + -ion-, -io -ion; akin to Latin quattuor four — more at four

1. : a set of four parts, things, or persons : tetrad

delivered him to four quaternions of soldiers — Acts 12:4 (Authorized Version)

the leading quaternion of publishers — Times Literary Supplement

2.

a.

(1) archaic : a sheet of paper folded twice

(2) : quire 1a

b. : a sheet that is folded once to form two leaves or four pages and nested together with other sheets (as in ancient books) to form a section

3. : a generalized complex number that is the sum of a real number and a vector and that depends on one real and three imaginary units the third of which is the product of the first two and also the negative of this product when the order of the factors is reversed so that multiplication over the field of quaternions is not commutative

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.