Dean comes from the old French deien, from the Latin decanus "head of a group of 10 monks in a monastery", from earlier secular meaning "commander of 10 soldiers" (which was extended to civil administrators in the late empire), a transliteration of the Greek decanos [Gr: δεκανός], from deca "ten". College sense is from 1570s.
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In modern Greek:
a) deca: ten [Gr: δέκα]
b) deca-: deca- [Gr: δέκα-] (decathlon, decalogue etc.)
c) decaneas: corporal, leader of ten soldiers [Gr: δεκανέας]
