Suggested to be a nominalization of a lost adjective, possibly from *sunnaz(“sunny”) + *-ô(agent suffix), from Proto-Indo-European*sh₂un-wó-s, from *sóh₂wl̥ ~ *sh₂wéns(“sun”) + *-wós,[1] or leveled from earlier paradigm *sundō ~ *sunᵈnaz, from *sundaz(“sunny”) + *-ô(agent suffix). from *sh₂un-tó-s, from *sóh₂wl̥ ~ *sh₂wéns + *-tós.[2] Feminine *sunnǭ(“sun”) perhaps constructed in an opposing gender pair with masculine *mēnô(“moon”), akin to Latin cognate sōlm(“sun”) and lūnaf(“moon”).[3][4]
^ Ringe, Donald (2006) From Proto-Indo-European to Proto-Germanic (A Linguistic History of English; 1)[1], Oxford: Oxford University Press, →ISBN, page 136
↑ 2.02.1Hilmarsson, Jörundur (1987) “Reflexes of I.-E. *suH2n̥to-/-ōn ‘sunny’ in Germanic and Tocharian”, in Sprache 33, pages 56–78
↑ 3.03.13.2Franck, Johannes (1892) “zon”, in Etymologisch woordenboek der nederlandsche taal (in Dutch), The Hague: 's-Gravenhage: Martinus Nijhoff: “Germ. *sunnô(n)-”
↑ 4.04.1Wodtko, Dagmar S., Irslinger, Britta, Schneider, Carolin (2008) “*séh₂u̯el-, *sh₂(u)u̯en-(?), *sh₂un-, ·suh₂l-”, in Nomina im indogermanischen Lexikon [Nouns in the Indo-European Lexicon] (in German), Heidelberg: Universitätsverlag Winter, page 606: “germ. *sunn-an- in got. DSg. sunnin, as. ahd. sunno m.”
