In Quenya, -rin is the generic ethnic adjectival suffix. Adjectives formed with it are used specifically in reference to ethnic groups. For instance, Sindarin is a combination of Sinda-rin, meaning "of the Sindar". Like many Quenya adjectives, words with this suffix can also be fashioned into nouns.
-rin can also be used to describe the languages of those ethnic groups. The word Sindarin can thus also mean "language of the Sindar", as a noun or adjective. However, it seems to be only used as a language-denoting suffix in reference to ethnic groups; the more generic suffix -ya is used as a suffix for languages describing geographical distribution, non-ethnic distinction, or very broad categories; for example:
- Amanya, "of Aman", referring to languages and dialects particular to the region of Aman.
- Quenya, "of persons (in general)", from a time when Elves were the only people they knew of who spoke language at all.
When different ethnic groups became differentiated (such as during the Sundering of the Elves), the language-denoting suffix was used to synthesize adjectives referring to these peoples, and also to their languages. But as time went on, the Quenya language still referred to their own language using -ya rather than -rin.
When suffixed to a noun that ends with r, the r vanishes, so that -r-rin becomes -rin rather than -rrin.
- Avarin (Avar-rin)
- Falmarin (Avar-rin)
- Nandorin (Nando-rin)
- Ñoldorin (Ñoldo-rin)
- Sindarin (Sinda-rin)
- Telerin (Teler-rin)
- Valarin (Vala-rin)
- Vanyarin (Vanya-rin)
 See also
- -ya (generic adjectival suffix)