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 

sambe

noun. room, chamber

A word for “room, chamber” in The Etymologies from around 1937, derived from primitive ᴹ✶stambē and cognate to N. tham “hall” under the root ᴹ√STAB (Ety/STAB).

Conceptual Development: This word first appeared as ᴱQ. sambe “chamber, room” in the Qenya Lexicon of the 1910s derived from the early root ᴱ√SAMA (QL/81), and appeared as ᴱQ. sambe “chamber” in the contemporaneous Poetic and Mythological Words of Eldarissa (PME/72). Its Gnomish equivalent G. tham “chamber, room” indicate the root form was actually ✱ᴱ√ÞAMA (GL/72). It reappeared as sambe “room, chamber” in the English-Qenya Dictionary from the 1920s (PE15/76). Its primitive form was given as ᴹ✶sambē “room” in the Declension of Nouns from the early 1930s (PE21/17), but this became ᴹ✶stambē in The Etymologies as noted above.

The Sindarin word sammath “chambers” hint at another possible root change (LotR/942); see that entry for discussion.