Liftoff

n.energetic, hopefulprofessional

Meaning 1

The moment a rocket or spacecraft rises from its launch surface.

Reach for it when naming the physical start of powered flight in space contexts

At liftoff, the rocket climbed through a clear band of morning sky.

playful
blastoff
dramatic rocket departure suits an excited account
not when Blastoff emphasizes spectacle and sounds informal in technical reporting.
everyday
takeoff
an aircraft or vehicle leaves the ground
not when Takeoff is standard for airplanes; rockets give liftoff its distinctive association.
professional
launch
the whole event of sending a vehicle into flight is meant
not when Launch includes preparation and release, whereas liftoff is the instant upward motion begins.
formal
ascent
the upward phase after departure is under discussion
not when Ascent is a continuing climb, not its starting moment.

The point at which a project or activity begins to gain real momentum.

Reach for it when using the launch image for an initiative that has moved beyond preparation

The first hundred subscribers gave the community journal real liftoff.

everyday
kickoff
an organized activity formally begins
not when Kickoff marks a start but offers no evidence that the project has gained momentum.
warm
breakthrough
a decisive advance makes progress possible
not when Breakthrough may occur long after a project has already begun.
professional
traction
adoption or support is now visibly growing
not when Traction describes response over time rather than the initiating point.

seconds before liftoff
The guidance computer completed its check seconds before liftoff.
successful liftoff
Successful liftoff began a six-month journey to the asteroid.
achieve liftoff
The repair cooperative achieved liftoff after the town awarded its first contract.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.