Mōnaþ (monath) is the Old English word for month. In compounds it means moon or lunar.
Lunar calendars mostly begin with the new cycle ― with the return of prosperity ― spring.
Of course, in actuality, there is neither beginning nor end.
Much like with any story, the choice of beginning determines the presumed end of the cycle, thus affecting the narrative for the particular choice.
also: prime-temps
Middle English springing time
Old English lencten
English
vernal
"pertaining to spring"
Latin
ver
"spring; spring-time of life, youth"
Middle English somer
Old English sumor
Ancient Greek
θέρος (théros)
"hottest season; summer"
Middle English harvest
Old English hærfest
"autumn, harvest-time; August"
Latin
autumnus
"autumn fruits, harvest; autumn"
Ancient Greek
ὀπώρα (opṓra)
"autumn; fall"
However, in figurative use, it means "summer-bloom, the bloom of youth"
It was the part of the year between the rising of Sirius and of Arcturus (i. e. the end of July, all August and part of September), the end of summer; later it was used for autumn.
Latin
chimerinus/-a/-um
"of winter"
Ancient Greek
χειμών (cheimṓn) noun
"winter"