rondnoun. cave roof
rondnoun. vaulted or arched roof, as seen from below (and usually not visible from outside), or a (large) hall of chamber so roofed
n. cave. Q. rondo.
grothnoun. cave, tunnel, large excavation
grothnoun. delving, underground dwelling
n. cave, mine, underground dwelling. Q. felco. Q.
1) grôd (i **rôd, construct grod) (delving, excavation, underground dwelling), pl. grŷd (in grŷd) (WJ:414), 2) groth (i **roth) (delving, large excavation), pl. gryth (in gryth) (VT46:12), 3) rond (construct ron) (cavern, vault, vaulted ceiling, hall with vaulted roof), pl. rynd (idh rynd), coll. pl. ronnath, 4) roth (delving, large excavation), pl. ryth, 4) gathrod (i **athrod), pl. gethryd (i ngethryd = i ñethryd), 5) fela (pl. fili). In the Etymologies (LR:381 s.v. PHÉLEG) the name Felagund is said to include this word, but since Tolkien later re-explained this name as a borrowing from Dwarvish, some would consider fela** as a word for ”cave” conceptually obsolete.
rhaw (?i thraw or ?i raw the lenition product of rh is uncertain) (flesh), pl. rhoe (?idh roe). Note: a homophone means ”wild, untamed”. (MR:350).