Why is the ninth month called September?
mid-14c., in religious use, "building up of the soul," from Old French edification and directly from Latin aedificationem (nominative aedificatio) "construction, building," in Late Latin "spiritual improvement," from past participle stem of aedificare (see edifice). Religious use is as translation of Greek oikodome in I Cor. xiv. Meaning "mental improvement" is 1650s. Literal sense of "building" is rare in English.