The mother-name of Finarfin (PM/360), and also the mother name of his son Finrod (PM/346). It is an archaic combination of the definite article i “the” and ✶Ñgoldō > Noldo, with the ñg- preserved because it was not at the beginning of the word (PE19/76). It would have been Sindarized as S. Angolodh, but this name was not used because Finarfin did not go to Middle-earth with his brothers (PM/360). A similar name was common in Númenor and Gondor, where it was reduced to Ingold (PM/360, LotR/749).
Conceptual Development: In earlier writing, the mother-name of Finarfin was Ingalaurë, while Ingoldo was the mother-name of Fingolfin (MR/230, PE17/118). At this stage, Tolkien said that it was a combination of the names of the peoples of Fingolfin’s mother and father, the Ingar and Noldor (MR/230). As the mother-mame of Fingolfin, Tolkien also considered having this name develop into Fingoldo (PE17/39) or Ingoldofinwe (PE17/118, MR/230) to better match his Sindarin name.
Ingoldo masc. name; possessive Ingoldova "Ingoldo's" (VT39:16)