A neologism coined by Paul Strack in 2018 specifically for Eldamo, an abstract elaboration of carth “deed”.
Sindarin
carth
noun. deed
carthas
noun. activity
cardh
deed
cardh (i gardh, o chardh), pl. cerdh (i cherdh). Note: cardh may also mean "house, building".
cardh
deed
(i gardh, o chardh), pl. cerdh (i cherdh). Note: cardh may also mean "house, building".
carn
noun. deed
pant
complete
pant (lenited bant; pl. paint) (full, whole); COMPLETELY, see
nuitha
prevent from coming to completion
(i nuitha, in nuithar) (stunt; stop short; not allow to continue) (WJ:413)
pant
complete
(lenited bant; pl. paint) (full, whole);
úgarth
ill deed
(sin), pl. úgerth (VT44:23)
Sindarin noun for a “deed”, attested only in its lenited plural form gerth within the word úgarth “trespass” (VT44/28), which probably more literally means “✱misdeed”. This word is not completely compatible with its Quenya cognate Q. carda “deed” from primitive ✶kardā, which in Sindarin should produce ✱cardh. Perhaps the Sindarin word had a slightly different primitive form ✱✶kartā. The expect form cardh might appear as an element in the variant form athragarð of S. athragared “interaction”.
Conceptual Development: Perhaps the earliest precursors of this word are G. cara “deed, act” and G. carm “act, deed, exploit” in the Gnomish Lexicon from the 1910s (GL/25; PE13/111), the latter a cognate of contemporaneous ᴱQ. karma “shape, fashion; act, deed” (QL/45). Early Noldorin word lists from the 1920s had ᴱN. carbh “deed” (PE13/140), reflecting Tolkien’s changing conception of the phonetic development of final -m in Noldorin. In The Etymologies from the 1930s, the word appeared as N. carth or carð “deed” (cardh), but these forms were rejected and replaced by N. car(ð) “building” when Tolkien decided the root meant only “make, build” and not “do” (Ety/KAR), a decision he later reversed.