The original name of Cabed Naeramarth before Nienor leapt to her death (S/224), translated “Deer’s Leap” (UT/150). It is a combination of cabed “leap”, en “of the” and aras “deer”.
Conceptual Development: In Silmarillion revisions from the 1950s-60s, this name was first written Mengas Dûr, quickly revised Cabad-en-Aras with an a in the last syllable of the first word, and finally changed to Cabed-en-Aras with an e (WJ/156).
cabed (ger. of cab- “leap”) + en (gen. article) + aras (“deer”)