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!

Qenya 

rondo

noun. roof; cave, cavern

Qenya [Ety/ROD; EtyAC/ROD; PE21/08] Group: Eldamo. Published by

tópa

noun. roof

A noun for “roof” in The Etymologies of the 1930s under the root ᴹ√TOP “cover, roof” (Ety/TOP).

Conceptual Development: The Qenya Lexicon of the 1910s had a similar form ᴱQ. túpo “roof, cover, lid” under the early root ᴱ√TUPU (QL/95), with just the gloss “roof” in the contemporaneous Poetic and Mythological Words of Eldarissa (PME/95). It also had a couple of other unrelated words: ᴱQ. tel (teld-) “roof” and ᴱQ. telin (telimb-) “roof, covering” both derived from the early root ᴱ√TELE (QL/90).