Wordnik Word of the Day for March 30, 2021

vertumnus

1. noun An ancient Roman deity who presided over gardens and orchards, and was worshiped as the god of spring or of the seasons in general. from The Century Dictionary.

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The word ‘vertumnus’ comes ultimately from a Latin word meaning ‘turn, change’.

it’s one of those times i re-discover my iconoclasm: is the relationship to Autumn not obvious?

autumn (n.)

season after summer and before winter, late 14c., autumpne (modern form from 16c.), from Old French autumpne, automne (13c.), from Latin autumnus (also auctumnus, perhaps influenced by auctus “increase”), which is of unknown origin. Perhaps from Etruscan, but Tucker suggests a meaning “drying-up season” and a root in *auq- (which would suggest the form in -c- was the original) and compares archaic English sere-month “August.” De Vaan writes, “Although ‘summer’, ‘winter’ and ‘spring’ are inherited IE words in Latin, a foreign origin of autumnus is conceivable, since we cannot reconstruct a PIE word for ‘autumn'”.

like, “VER” is obviously green, as in verdant,
and opposite to “AU”
which leaves “TUMN” as a root meaning change

Since the other etymologies for autumn
are educated SWAGs,
i would offer my opinion that
“AU” comes from “AUR” (gold)
also relating to the color of leaves in season
if you see how i mean . . .

and, not for nuthin’ . . .
“summer” & “winter” are both proto-germanic, not latin,
but i am sure what he means
aestas, which comes from a Proto-Indo-European word meaning “to burn, or be on fire.”
and heimas, also PIE for “snow”