# How did “lambda” come to mean “average”? [duplicate]

I've just learned that "lambda" has the additional meaning of "average" or something close to that, which I find surprising. How did it come to acquire this meaning?

The Greek alphabet starts from "alpha" and ends with "omega". As for the lesser-known "lambda", it comes in the 11th place among all 24 letters.

The midpoint is the 12th/13th letters, to which "lambda" is placed closest, hence the idea of holding an "average" position in the grand scheme of things.

If you land at the 11th/12th/13th/14th spot out of 24 competitors, you will reasonably qualify as "average/lambda", being close to neither the victor "alpha" nor the "omega" finishing last.

I'd say something like:

Une grande chance comme ça n'arrive qu'une seule fois dans la vie de quelqu'un lambda comme moi !

.

• Merci, Monsieur. C'est cool. – ktm5124 Oct 28 '17 at 21:09
• So you're saying the French consider the 11lth letter closer to the position between the 12th and the 13th letter than either the 12th or the 13th? – sgf Oct 28 '17 at 22:33
• @sgf Hi. Considering that "average" is a notion referring to a certain range around the midpoint instead of the exact midpoint, I find it just as logical to use the 11th letter as the 12th/13th. For instance, "an average age of 50" can represent a range of "45-55". So it does not necessarily have to be exactly 50 or the closest 49/51, but can also be 48/52 just as well to qualify as the notion of "average/lambda". – Con-gras-tue-les-chiens Oct 29 '17 at 1:11
• @sgf Yes, polytechniciens are well known to be bad at maths... – jlliagre Oct 29 '17 at 7:49
• @sgf It might be because 12th and 13th places "mu" and "nu" both already mean something in French. – meristel Oct 29 '17 at 11:32

Précisément, l'usage de lambda comme "moyen" provient de l'école polytechnique