Gnomish
raith
noun. extent, reach; region, sphere, district; scope
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
The noun G. raith appeared in the Gnomish Lexicon of the 1910s, with glosses “extent, reach; region, sphere, district; scope” (GL/65). It was likely based on the early root ᴱ√RAHA “stretch forward” (QL/32, 78). A similar form ᴱN. rhaith appeared in Early Noldorin Word-lists of the 1920s, but without any gloss (PE13/152).
Neo-Sindarin: For purposes of Neo-Sindarin, I would update this noun to ᴺS. raeth, basing it on the later root ᴹ√RAK “stretch out, reach” with the Sindarin phonological result of *aeth* < *aith* from the vocalization of ancient *akt(h)*. I would use it only for the senses “extent, reach, scope”, since there are plenty of later attested words for things like “region, sphere, district”.