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

gwel-

verb. to boil; to bubble (intr.)

A verb appearing as G. gwel- in the Gnomish Lexicon of the 1910s with the glosses “boil” and “bubble (intr.)” (GL/44). It is clearly based on the early root {ᴱ√WELE >>} ᴱ√GWELE from the contemporaneous Qenya Lexicon (QL/103).

Neo-Sindarin: Since we have no better “boil” words, I retain ᴺS. gwel- “to boil, bubble” for purposes of Neo-Sindarin, but assume it is derived from a Neo-Root ᴺ√WEL so that it retains the same form.