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.

Gnomish

belu-

verb. to unroll, unfurl (intransitively), belly (of sails), swell

A verb appearing as belu- or belwa- in the Gnomish Lexicon glossed “unroll, unfurl (intransitively), belly (of sails), swell” in the Gnomish Lexicon of the 1910s (GL/22), clearly based on the early root ᴱ√VELU (or ✱ᴱ√BELU) “unroll” (QL/100).

@@@ maybe salvage belwa-?

belwa-

verb. to unroll, unfurl (intransitively), belly (of sails), swell

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.