(1) One of the primary reasons to go backpacking is that it feels really good when you stop, and one of those times is around the middle of the day, when you can both stop and also eat. This activity is called "lunch", and since you will be outdoors when you do it, you are thereby officially out to lunch.
(2) A merging of the terms "lunge" and "lurch". What you do when you are standing somewhere and eating a big messy sandwich full of tasty, wet and sloppy goodness and the filling just sort of foops out of your hand and heads for the ground. Even if you are successful at catching it you will still be at least a little upset, and your hands will be messy, though you will still be fed. If you do catch it.
(3) A meal at midday, especially when not the main meal of the day. Any small meal, especially at a social gathering.
(4) A mid-day repast, dating from 1829. This is a shortened form of "luncheon", originally from the 1650s, referring to a noonish-to-afternoon meal eaten by those whose main meal is eaten about then.
(5) "Out to lunch" is slang. Its meaning of insane, stupid, or clueless was first recorded 1955. Applies to backpackers as well.
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Etc...
so says eff: sporadic spurts of grade eff distraction
definitions: outdoor terms
fiyh: dave's little guide to ultralight backpacking stoves
boyb: dave's little guide to backpacks
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