S. groth n. “large excavation, delving, underground dwelling” (Category: Cave)
A noun for a large excavation (WJ/415) or a cave or tunnel (EtyAC/ROT) with variants groth and grod, the former seen in names like Menegroth “Thousand Caves” and the latter in names like Novrod “Hollow-delving” (later Nogrod “Dwarf-delving”). It was derived from strengthened forms ✶grottā or grotā of the root √ROT (WJ/414-415).
Conceptual Development: The earliest iteration of this word was (archaic) G. †roth “cave, grot” from the early root ᴱ√roto (GL/65); this root was glossed “hollow” in the contemporaneous Qenya Lexicon (QL/80). Both strengthened and unstrengthened variants N. groth and roth “cave, tunnel” appeared under the root ᴹ√ROT “bore, tunnel”, a late entry to The Etymologies of the 1930s (EtyAC/ROT). Suffixal forms -roth, -rod were mentioned in passing in Words, Phrases and Passages from the Lord of the Rings from the late 1950s or early 1960s as derivatives of √ROT “cave” in connection to the name S. Nimrodel (PE17/49).
A fairly lengthy discussion of these words appeared in the Quendi and Eldar essay from 1959-60 (WJ/414-415), where Tolkien gave the root form as √groto “dig, excavate, tunnel” contrasted with √rono “arch over, roof in”. Tolkien also compared groth/grod to S. rond “vaulted or roofed chamber”, only the latter of which “could be applied both to natural and to artificial structures”. Of the two Tolkien said:
Though distinct in origin the derivatives of *groto and *rono naturally came into contact, since they were not dissimilar in shape, and a *rondō was usually made by excavation. Thus S groth < *grottā (an intensified form of grod < *grotā) “a large excavation” might well apply to a rond. Menegroth means “the Thousand Caves or Delvings”, but it contained one great rond and many minor ones (WJ/415).
Neo-Sindarin: Despite Tolkien’s comments in the Quendi and Eldar essay, there are some cases where grod/groth seems to apply to natural caves as well as excavated ones, such as Nimrodel “Lady of the White Cave” and Androth “*Long Cave”. As such, I would use it for both natural and excavated caverns.
References ✧ PE17/49; SA/groth, naug; WJ/414-415
|#-rod||soft-mutation; g-mutation||✧ SA/groth|
|-rod||soft-mutation; g-mutation||✧ WJ/414|
|√ROT > -roth/rod||[-rottā] > [-rotta] > [-rottʰa] > [-roθθa] > [-roθθ] > [-roθ]||✧ PE17/49|
|✶(g)rotā > grod||[grotā] > [grota] > [grot] > [grod]||✧ WJ/414|
|✶grottā > groth||[grottā] > [grotta] > [grottʰa] > [groθθa] > [groθθ] > [groθ]||✧ WJ/415|
References ✧ EtyAC/ROT
|ᴹ√ROT > roth||[rotto] > [rottʰo] > [roθθo] > [roθθ] > [roθ]||✧ EtyAC/ROT|
|ᴹ√ROT > groth||[grotto] > [grottʰo] > [groθθo] > [groθθ] > [groθ]||✧ EtyAC/ROT|
References ✧ GL/65; LT2A/Rothwarin