eat someone's lunch

Possibly from the idea of a stronger or quicker person snatching away and eating another person’s lunch before they can consume it.

• (Received Pronunciation) IPA^(key): /ˈiːt ˌsʌmwʌnz ˈlʌnt͡ʃ/, /-ˈlʌnʃ/
• (General American) IPA^(key): /ˈit ˌsʌmwʌnz ˈlʌnt͡ʃ/, /-ˈlʌnʃ/

• Audio (General Australian):

  (file)

• Rhymes: -ʌntʃ

eat someone's lunch (third-person singular simple present eats someone's lunch, present participle eating someone's lunch, simple past ate someone's lunch, past participle eaten someone's lunch)

1. (idiomatic, chiefly US, slang) To best or defeat someone thoroughly; to make short work of.

   Synonyms: eat someone for breakfast, have someone for breakfast; see also Thesaurus:defeat

   • 2006 October 2, “A Disastrous ‘Upgrade’: My Boss Insisted that Creating a Windows Version of Our DOS App would Ensure Our Future”, in Steve Fox, editor, InfoWorld, volume 28, number 40, San Francisco, Calif.: InfoWorld Publishing Co., International Data Group, →ISSN, →OCLC, page 52, column 1:

     So in a classic it-ain't-broke-so-let's-fix-it-anyway move, some of our managers and salespeople began complaining that it wasn't written for Windows. […] If we didn't rewrite for Windows, they insisted, our competitors would eat our lunch!

   • 2010 November 18, Kate Sheppard, “Outgoing GOPer Slams Climate Denying Colleagues”, in Mother Jones‎, San Francisco, Calif.: Foundation for National Progress, →ISSN, →OCLC, archived from the original on 2023-08-18:

     "I would also suggest to my free enterprise colleagues—especially conservatives here—whether you think it's all a bunch of hooey [i.e., climate change], what we've talked about in this committee, the Chinese don’t," the South Carolina Republican [Bob Inglis] said in his opening remarks. "And they plan on eating our lunch in this next century."

   • 2011, Josh Linkner, “Gaining the Keys to a Creative Mind and Culture”, in Disciplined Dreaming: A Proven System to Drive Breakthrough Creativity, San Francisco, Calif.: Jossey-Bass, Wiley, →ISBN, step 2 (Prepare), page 102:

     It seemed inevitable: Slither was going to eat our lunch unless we upped our game and out-Slithered Slither. But here's the thing, The Slither Corporation doesn't actually exist. It's our fictive nemesis, our imaginary bad guys. Rather than battling a poorly performing company, we went up against our worst enemy—the company that we knew could put us out of business (if it really existed).

   • 2021 December 13, Molly Ball, Jeffrey Kluger, Alejandro de la Garza, “Time 2021 Person of the Year: Elon Musk”, in Time‎, New York, N.Y.: Time Inc., →ISSN, →OCLC, archived from the original on 2024-05-14:

     Today, thanks in large part to Musk's pace-setting, auto companies from VW to Nissan are jostling to invest billions in electric vehicles. Their about-face is driven less by altruism than by a dawning realization that Musk is eating their lunch.

   • 2023 September 27, Spencer Kornhaber, “The Weirdos Living Inside Our Phones”, in The Atlantic‎, Washington, D.C.: The Atlantic Monthly Group, →ISSN, →OCLC, archived from the original on 2023-12-30:

     Platforms such as TikTok and Instagram are, indeed, eating traditional comedy’s lunch lately when it comes to funny characters.

• Colin McIntosh, editor (2013), “eat someone’s lunch, idiom”, in Cambridge Advanced Learner’s Dictionary, 4th edition, Cambridge, Cambridgeshire: Cambridge University Press, →ISBN, reproduced in the Cambridge English Dictionary website, Cambridge: Cambridge University Press.
• “eat someone’s lunch”, in Collins English Dictionary.
• “eat someone’s or something’s lunch, idiom”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.