The act of having lunch with a co-worker other than your monogamous dining partner.
Chris: Where were you at lunch?
Paul: Oh, Rich and I went out to Donahue's for a steak and cheese.

Chris: Was I not at my desk when you left
Paul: No, you were there.

Chris: You just comitted lunch adultery. I hope you had to fake all of your laughs at his awful jokes!
by dOPARIS February 5, 2010
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