liftoff

/ˈlɪftˌɔf/
noun
  1. The moment when a spacecraft or rocket leaves the ground and begins to fly upward.
    • The crowd cheered as they watched the rocket's liftoff.
    • Liftoff is scheduled for 3:00 PM tomorrow.
    • The astronauts felt a strong vibration during liftoff.
  2. The beginning or launch of a project, event, or process.
    • The festival's liftoff was marked by a spectacular fireworks display.
    • We need a solid plan for the liftoff of our fundraising campaign.
    • The company celebrated the liftoff of its new product line.