(algebra) An integral domain which has a subset whose elements are said to be "positive", such that this subset is closed under addition, closed under multiplication, and all elements of the integral domain satisfy a law of trichotomy; namely, that either that element is in the said subset, or it is the zero (additive identity), or its product with −1 (the additive inverse of the multiplicative identity) belongs to the said subset.

(mathematics) An ordered field which satisfies the axiom of Archimedes.

(chemistry) The number of bonds between a pair of atoms in a molecule

An order that cannot be currently filled or shipped, but is requested nonetheless for when the item becomes available again.

To treat as a back order.

plural of Mary Bell order

(archaic) Third-person singular simple present indicative form of order

(military) The arrangement of units or other divisions of the armed forces in combat; specifically, the deployment plans of an enemy, or a written record of this.

(archaic) Third-person singular simple present indicative form of ordain

plural of co-ordinate axis