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

tubla-

verb. to hide (intr.)

A verb appearing as G. tubla- “hide (intr.)” in the Gnomish Lexicon of the 1910s, apparently based on G. tub- “cover” (GL/71) from the early root ᴱ√TUPU (QL/95).

Neo-Sindarin: Since √TUP “cover, hide” survives in Tolkien’s later writings, I would retain and adapt this Gnomish verb as ᴺS. tobla- “hide”, but would use it both transitively and intransitively.