Mmm. Actually, delta-v is the generic
term for any change in velocity
(delta = change; v = velocity) in any mechanics
equation. Any time you use the accelerator
(or the brakes) on your car, or for that matter even the steering wheel, you will experience delta-v relative to the Earth and objects around you.
Now, I'm not saying that WolfKeeper's use isn't the coolest use around, no no. In spacecraft, delta-V is sometimes used to refer to the amount of available energy for course change that the craft has remaining - it's more useful than knowing the amount of fuel or even the seconds of thrust left.