Eat Someone's Lunch Meaning

(idiomatic) To defeat or best thoroughly; to make short work of.

Example: 2006, "A Disastrous 'Upgrade'", InfoWorld, 2 October 2006:
  If we didn't rewrite for Windows, they insisted, our competitors would eat our lunch!
2010, Kate Sheppard, "Outgoing GOPer Slams Climate Denying Colleagues", Mother Jones, 18 November 2010:
  "I would also suggest to my free enterprise colleagues—especially conservatives here—whether you think it’s [climate change] all a bunch of hooey, what we've talked about in this committee, the Chinese don’t," the South Carolina Republican said in his opening remarks. "And they plan on eating our lunch in this next century."
2011, Josh Linkner, Disciplined Dreaming: A Proven System to Drive Breakthrough Creativity, Jossey-Bass (2011), ISBN 9780470922224, page 102:
  It seemed inevitable: Slither was going to eat our lunch unless we upped our game and out-Slithered Slither.