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

dultha-

verb. to dine

A verb in the Gnomish Lexicon of the 1910s glossed “to dine” based on a (hypothetical) early root ᴱ√DULU of similar meaning (GL/31).

dultha

noun. supper, dinner

A noun in the Gnomish Lexicon of the 1910s glossed “supper, dinner” related to G. dultha- “to dine”, possiblly based on a (hypothetical) early root ᴱ√DULU of similar meaning (GL/31).

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.