Pronunciation: (lift'ôf", -of"),[key] —n. 1. Aeron.,Rocketry. a. the action of an aircraft in becoming airborne or of a rocket in rising from its launching site under its own power.
b. the instant when such action occurs.
2. Informal.the launching or commencement of a project, plan, etc.: The liftoff of the sales campaign will be next month.
—adj. that removes by lifting off; capable of being lifted off: a liftoff correction tape for typewriters; magnetized, liftoff nameplates.Also,lift'-off".