Name adopted by Túrin while he was in Nargothrond, translated “Black Sword” (S/210), a combination of morn “black” and megil “sword” (SA/mor, EtyAC/MAK).
Conceptual Development: In the earliest Lost Tales, this name first appeared as G. Mormagli (LT2/84), revised to N. Mormaglir in early Silmarillion drafts from the 1930s, then to N. Mormael (SM/313, LR/139) alternating with N. Mormegil (SM/313). Mormegil appeared in an early entry of The Etymologies (EtyAC/MAK), with a later entry suggesting a replacement N. Magladhûr that was never used in the texts (Ety/MAK). It wasn’t until the Silmarillion revisions from the 1950s-60s that Tolkien finally settled exclusively on S. Mormegil (WJ/83, 138 note §268).
morn (“dark, black”) + megil (“sword”)