Sindarin name of the Isenmouth, translated “Iron Jaws” (LotR/920) or “Iron Mouth” (RC/772, PE17/101). This name is a combination of carach “jaws” and angren “iron” (SA/carak).
Conceptual Development: This name was already N. Carach Angren when it first appeared in Lord of the Rings drafts from the 1940s (SD/33).
A noun for “jaws, rows of teeth” (RC/607) appearing as an element in the name Carach Angren “Iron Jaws” (LotR/920), likely derived from the root √KARAK and probably a cognate to Q. caraxë.
Conceptual Development: N. Carach Angren was already translated “Jaws of Iron” when it first appeared in Lord of the Rings drafts from the 1940s (SD/33).
The Etymologies of the 1930s had N. -charaes as the equivalent of ᴹQ. karakse in Helcharaes under the root ᴹ√KARAK “sharp fang, spike, tooth” (Ety/KARAK). However, that may reflect differing phonetic developments between Sindarin and Noldorin, with Noldorin -akse > -ais(e) > -aes but Sindarin -akse > -ach; compare S. ach “neck” < aks[e] (PE17/92).