Its name comes from the words yávë ("fruit") and anna ("gift"), a reference to the harvests of autumn, and connected to the name of Yavanna, the Vala of earth and growth.
Sindarin
ivann
feminine name. Fruit-giver
ivanneth
noun. September, *Yavanna-ness
ivanneth
noun. september (month)
ivanneth
Ivanneth
ivanneth
september
Ivanneth
ivanneth
september
ivon
yavanna
(isolated from Ivonwin), also Ivann.
ivonwen
maiden of yavanna
pl. Ivonwin
Sindarin name of Yavanna.
Conceptual Development: In the Gnomish Lexicon from the 1910s, this name appeared as G. Ivon or Ifon (GL/18), and appeared as Ifan in the very early Silmarillion drafts from the late 1920s (SM/12). It appeared as N. Ivann in The Etymologies from the 1930s (Ety/YAB). It is not directly attested in Tolkien’s later writings, but appears as an element in the names Ivanneth “September, ✱Yavanna-ness” (LotR/1110) and Ivonwin “Maidens of Yavanna” (PM/404).