Summer
Old English sumor, of Germanic origin; related to Dutch zomer, German Sommer, also to Sanskrit samā ‘year’.
wiktionary
From Middle English somer, sumer, from Old English sumor(“summer”), from Proto-Germanic *sumaraz(“summer”), from Proto-Indo-European*sm̥-h₂-ó-, oblique of *semh₂-(“summer, year”). Cognate with Scots somer, sumer, simer(“summer”), West Frisian simmer(“summer”), Saterland Frisian Suumer(“summer”), Dutch zomer(“summer”), Low German Sommer(“summer”), German Sommer(“summer”), Danish and Norwegian Bokmål sommer(“summer”), Swedish sommar(“summer”), Norwegian Nynorsk and Icelandic sumar(“summer”), Welsh haf(“summer”), Armenian ամ(am, “year”), ամառ(amaṙ, “summer”), Sanskrit समा(sámā, “a half-year, season, weather, year”), Northern Kurdish havîn(“summer”), Central Kurdish ھاوین (hawîn, “summer”).
From Middle English somer, from Anglo-Norman summer, sumer, from Vulgar Latin saumārius, for Late Latin sagmārius, from Latin sagma(“sum”). Compare sumpter.
sum + -er
etymonline
summer (n.1)
"hot season of the year," Old English sumor "summer," from Proto-Germanic *sumra- (source also of Old Saxon, Old Norse, Old High German sumar, Old Frisian sumur, Middle Dutch somer, Dutch zomer, German Sommer), from PIE root *sm- "summer" (source also of Sanskrit sama "season, half-year," Avestan hama "in summer," Armenian amarn "summer," Old Irish sam, Old Welsh ham, Welsh haf "summer").
As an adjective from c. 1300. Summer camp as an institution for youth is attested from 1886; summer resort is from 1823; summer school first recorded 1810; theatrical summer stock is attested from 1941 (see stock (n.2)). Old Norse sumarsdag, first day of summer, was the Thursday that fell between April 9 and 15.
summer (n.2)
"horizontal bearing beam," late 13c., from Anglo-French sumer, Old French somier "main beam," originally "pack horse," from Vulgar Latin *saumarius, from Late Latin sagmarius "pack horse," from sagma "packsaddle" (see sumpter).
summer (v.)
"to pass the summer," mid-15c., from summer (n.1). Related: Summered; summering.
