Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!

Gnomish

igli

noun. young of fish, small fry

A noun appearing as G. igli “young of fish, small fry” in the Gnomish Lexicon of the 1910s, an elaboration of G. ing “fish” (GL/51).

Neo-Sindarin: For purposes of Neo-Sindarin I’d adapt this as ᴺS. limmeg “young fish, small fry”, a diminutive of ᴺS. lim “fish”.