In the Qenya Lexicon of the 1910s, ᴱQ. Ion was the “mystic name of God, 2nd Person of Blessed Trinity”, that is the “Son” in the “Father, Son, Holy Ghost” trinity (QL/43). In that document yon or yond- was given in a couple of places as (archaic?) words for “son” (QL/43, 106). In Early Noldorin Word-lists of the 1920s, Tolkien gave ion as the equivalent of ᴱN. gó “son”, along with a plural form yondi (PE13/113). However, in the English-Qenya Dictionary Tolkien said yondi was an irregular plural form of ᴱQ. yondo “son” (PE15/77), and this is the form he typically used in later writings.