noun. A set of four persons or items.

noun. 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 multiplication is not commutative.

noun. A set, group, or body of four: applied to persons or things.

noun. A word of four syllables; a quadrisyllable.

noun. A fourfold quantity capable of being expressed in the form xi + yj + zk + w, where x, y, z, w are scalars, or real numbers, while i, j, k are vectors, or quantities whose squares are negative scalars. The calculus of such quantities is termed quaternions.

To divide into quaternions, files, or companies.

noun. In book-making, a set or ‘gathering’ of four sheets of paper or parchment folded in two.

noun. The number four.

noun. A set of four parts, things, or person; four things taken collectively; a group of four words, phrases, circumstances, facts, or the like.

noun. A word of four syllables; a quadrisyllable.

noun. 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.

transitive verb. To divide into quaternions, files, or companies.

noun. the cardinal number that is the sum of three and one

"Outside the quaternion were the dancing Pauppukkeewis, the Whirlwind, and the fierce and shifty hero, Monobozho, the North-West"