This hyphenated word is made from two common words. Tolkien never uses “dining room” as two separate words. We may be certain that in Bilbo’s native language there was a specific – and probably important! – word for dining-room, not just some subcategory of “room”.
- 01.002 dining-rooms,
- 02.001 went into the dining-room.
- 02.002 in the kitchen before turning out the dining-room.
- 02.002 in the dining-room by the open window,
- 04.012 in Bilbo’s dining-room that seemed so long ago,
Just updating this entry to note that it’s a food word just as much as cellar or pantry is!