Sowilō

Name
	"Sun"
Shape	Elder Futhark	Futhorc	Younger Futhark
Unicode	ᛊ U+16CA	ᛋ U+16CB		ᛌ U+16CC
Transliteration	s
Transcription	s
IPA	[s]
Position in rune-row	16		11

*Sowilō or *sæwelō is the reconstructed Proto-Germanic language name of the s-rune, meaning "sun". The name is attested for the same rune in all three Rune Poems. It appears as Old Norse sól, Old English sigel, and Gothic sugil.

The Germanic words for "Sun" have the peculiarity of alternating between -l- and -n- stems, Proto-Germanic *sunnon (Old English sunne, Old Norse, Old Saxon and Old High German sunna) vs. *sôwilô or *saewelô (Old Norse sól, Gothic sauil, also Old High German forms such as suhil).

This continues a Proto-Indo-European alternation *suwen- vs. *sewol- (Avestan xweng vs. Latin sōl, Greek helios, Sanskrit surya, Welsh haul, Breton heol, Old Irish suil "eye"), a remnant of an archaic, so-called "heteroclitic", declension pattern that remained productive only in the Anatolian languages.

The Old English name of the rune, written sigel (pronounced /ˈsɪ.jel/) is most often explained as a remnant of an otherwise extinct l-stem variant of the word for "Sun" (meaning that the spelling with g is unetymological), but alternative suggestions have been put forward.

The Elder Futhark s rune (reconstructed name *Sowilo) is attested in two variants, a Σ shape (four strokes), more prevalent in earlier (3rd to 5th century) inscriptions (e.g. Kylver stone), and an S shape (three strokes), more prevalent in later (5th to 7th century) inscriptions (e.g. Golden horns of Gallehus, Seeland-II-C).

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