jǫstr

Old Norse

Etymology

From Proto-Germanic *jestuz. Note that the j- in this word is not etymological, but comes from breaking; in Proto-Norse, j- was always lost word-initially. Thus, the development of the nominative has been *jestuʀ > *estuʀ > *eastuʀ > jǫstr, with U-mutation visible.

Noun

jǫstr m (genitive jastar, dative isti)

1. yeast

Declension

  Declension of jǫstr (strong u-stem, singular only)

masculine	singular
	indefinite	definite
nominative	jǫstr	jǫstrinn
accusative	jǫst	jǫstinn
dative	isti	istinum
genitive	jastar	jastarins

Synonyms

• gerð

Related terms

• œsa

Descendants

• Icelandic: jöstur
• Norwegian Nynorsk: jester, jest
• Norwegian Bokmål: jest
• Old Swedish: iæster
  • Swedish: jäst

References

• jöstr in A Concise Dictionary of Old Icelandic, G. T. Zoëga, Clarendon Press, 1910, at Internet Archive.