(Mathematics)a complex number of the form w + xi + yj + zk, where w, x, y, z are real numbers and i, j, k are imaginary units that satisfy certain conditions (数)四元数
(rare)a set of four people or things (罕)四人组;四件套
语源
mid 19th cent.: from late Latin quaternio(n-), from Latin quarterni (see quaternary)