Last month I wrote that I would come back to English harvest, Danish høst and the Norwegian innhøsting. Those words are related to herfst, the Dutch word for autumn. In fact, in Old English the word hærfest was used for what is now called autumn. All those words go back to the Proto-Germanic *harbusta-, which must have meant "time in which one picks". As August is the harvest month, you could call autumn the harvest season.

Autumn starts in September; in that word you can clearly recognize that with the Romans it was the seventh month. The Latin word septem is the closest of all languages to the Proto-Indo-European stem *septm, but in the other languages the relationship is also clearly visible.

Incidentally, autumn is only known to come from Latin via French, but the original meaning is unknown. Finally, in the Danish efterår I recognize - thinking of English (after and year) and Frisian - the Dutch synonym of herfst: najaar.