(mathematics) Any of a set of fundamental axioms describing the natural numbers and their relationships.

(automotive, mechanical engineering) An axle supporting only one wheel of a pair on opposite sides of a vehicle.

plural of axle weight

The total weight placed upon an axle and its attached wheels, which is transmitted to a road or rail surface.

plural of Axel

plural of axle-box

Alternative spelling of axlebox.

(astronomy) The axis of Earth between the celestial poles, important in ancient geocentric coordinate systems.

(electronics, chiefly attributive) An electrical component with two leads (wires) extending out in opposite directions (along a single axis).

plural of axial lead