Delta-v Definition

noun

(physics) A vector change in velocity, especially a small change as a result of a corresponding change in some other parameter.

Wiktionary

(astronautics) The maximum change in the scalar speed of a rocket if the rocket were operated in a vacuum away from external forces.

Wiktionary

(astronautics) A minimum scalar requirement for rocket delta-v to be able to achieve a particular manoeuvre.

Wiktionary