Alternate Definition:
A leisure lunch taken with other proffessionals for the purposes of buisness. Often with clients or coworkers. 3 martini's = 3 hours.

Modern equivlant is two martini lunch which means to have a short three martini lunch
Bob and Susan took their clients out for a three martini lunch to discuss future products releases.
by AA March 22, 2005
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The three martini lunch, otherwise known as the alcoholics version of a two martini lunch. Generally used to refer to people who have too much time and nothing to do with it (see example).
Person A: "Man, fedex isn't going to deliver the package i need till 2:00!"

Person B: "Well then, go have yourself a three martini lunch!"
by AA March 22, 2005
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