Quenya 

-ndil

friend

-ndil (also -dil) ending occurring in many names, like Amandil, Eärendil; it implies devotion or disinterested love and may be translated "friend" (SA:(noun)dil); this ending is "describing the attitude of one to a person, thing, course or occupation to which one is devoted for its own sake" (Letters:386). Compare -ndur. It is unclear whether the names derived with the ending -ndil are necessarily masculine, though we have no certain example of a woman's name in -ndil; the name Vardilmë (q.v.) may suggest that the corresponding feminine ending is -(n)dilmë.