A verb glossed “shatter” in the Gnomish Lexicon of the 1910s (GL/64), perhaps based on the early root ᴱ√RAKA “pile up”, though the meaning doesn’t match (QL/78).
Gnomish
ractha
noun. breach
ractha-
verb. to shatter
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 appearing as G. ractha “breach” in the Gnomish Lexicon of the 1910s, related to the verb G. rag- “break asunder, burst” (GL/64).
Neo-Sindarin: Since I retain ᴺS. rag- “to break (asunder), burst”, I would keep this noun as well, but I would update it to ᴺS. raeth “breach, ✱burst” to better fit Sindarin phonology.