Search Result for "liftoff": 
Wordnet 3.0

NOUN (1)

1. the initial ascent of a rocket from its launching pad; 



The Collaborative International Dictionary of English v.0.48:

liftoff \liftoff\ n. (Rocketry)
   the initial ascent of a rocket from its launching pad.
   [WordNet 1.5]


WordNet (r) 3.0 (2006):

liftoff
    n 1: the initial ascent of a rocket from its launching pad