From Tolkien Gateway

-il is a little-attested ending in the Sindarin language,[note 1] used sometimes to denote feminine gender. Its masculine counterpart is -on.

Its presence causes i-affection to the vowels of the stem (cf. brannon and brennil).


Possibly it derives from a Common Eldarin ending *-illê. This is supported by several Quenya words which end in -illë with Sindarin cognates in -il; most notably compare the Quenya amille "mother" and the Sindarin emil.


In at least one case, -il is said to be a diminutive ending; compare how the masculine ending -on can sometimes refer to "great" things.


  1. Some of the examples refer to Noldorin as well