Why is the ninth month called September?
"art of moving, quartering, and supplying troops," 1879, from French (l'art) logistique "(art) of quartering troops," from Middle French logis "lodging," from Old French logeiz "shelter for an army, encampment," from loge (see lodge (n.)) + Greek-derived suffix -istique (see -istic). The form in French was influenced by logistique. Related: Logistical.
"pertaining to logic," 1620s, from Medieval Latin logisticus, from Greek logistikos "endued with reason," from logikos (see logic). Related: Logistical (1560s); logistically. Logistics from this word, in the sense "art of arithmetical calculation" is from 1650s.