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definitions

liftoff

or lift-off

[lift-awf, -of]
See more synonyms for liftoff on Thesaurus.com
noun
  1. Aeronautics, Rocketry.
    1. the action of an aircraft in becoming airborne or of a rocket in rising from its launching site under its own power.
    2. 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.
adjective
  1. that removes by lifting off; capable of being lifted off: a liftoff correction tape for typewriters; magnetized, liftoff nameplates.

Origin of liftoff

First recorded in 1955–60; noun, adj. use of verb phrase lift off
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for lift off

escalate, climb, soar, blow, depart, withdraw, go, disappear, fly, rise, sprout, mount, float, scale, arise, tower, ascend, bear, begone, decamp
British Dictionary definitions for lift off

liftoff

noun
  1. the initial movement or ascent of a rocket from its launch pad
  2. the instant at which this occurs
verb lift off
  1. (intr, adverb) (of a rocket) to leave its launch pad
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for lift off

liftoff

n.

also lift-off, "vertical take-off of a rocket, etc.," 1956, American English, from lift (v.) + off.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with lift off

lift off

Begin flight, as in The spacecraft was due to lift off at ten o'clock. The off in this idiom means “off the ground.” [Late 1800s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.