A noun for “homestead” in the Gnomish Lexicon of the 1910s, a combination of G. bar “home” with the noun suffix G. -wen (GL/21).
Gnomish
osta-
verb. to surround with walls, build up; to fortify, protect; to surround
barwen
noun. homestead
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
A verb appearing as G. osta- “to surround with walls, build up; fortify, protect; surround” in the Gnomish Lexicon (GL/63), based on the early root ᴱ√OSO as suggested by Christopher Tolkien (LT2A/Belegost; QL/s71).
Neo-Sindarin: Since ᴹ√OS “round, about” appears in Tolkien’s later writings, I would retain ᴺS. osta- for purposes of Neo-Sindarin, originally with the sense “to surround”, later more specifically “surround with walls” and by extension “fortify, protect”, probably due to the influence ost “(fortified) town”.