Able to be decreased.

(mathematics, of a function) always decreasing or remaining constant, and never increasing; contrast this with strictly decreasing

(mathematics) Any function of a real variable whose value decreases (or is constant) as the variable increases.

plural of decreasing function

(mathematics) Any function of a real variable whose value decreases as the variable increases.

plural of strictly decreasing function

(insurance) Term assurance with a sum assured that decreases over the term of the contract.

In a decreasing manner; progressively less.