Early Noldorin
narog
adjective. violent (of water, rain, etc.), torrential
narog
place name. Torrent
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.
An adjective in Early Noldorin Word-lists of the 1920s glossed “violent (of water, rain, &c.), torrential” (PE13/150), likely the basis for the river name ᴱN. Narog “Torrent” from this time period (LB/61). This river name was given a new etymology in later writings (PE17/37) so the word ᴱN. narog “torrential” was likely abandoned.