Gnomish
flass
noun. sea-marge, surf; foam; margin, ragged margin, fringe
tholos
noun. sea-marge
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 noun in the Gnomish Lexicon of the 1910s glossed “sea-marge, surf; foam; margin, ragged margin, fringe” (GL/35), derived from the root ᴱ√fal- which was “connected with ... many words in fl-” (GL/33).