A word for “slayer” (PE17/97), a noun form of dag- “to slay” with the agental suffix -nir, appearing in the (somewhat loosely translated) phrase: Túrin Turambar Dagnir Glaurunga “Túrin Turambar, Glaurung’s Bane” (S/226). I would use this word as “bane” only in the sense of “one who has killed” or “one who will kill”.
Sindarin
dagnir
masculine name. *Slayer
dagnir
noun. slayer, bane
dagnir
noun. slayer
dagnir
noun. bane
Dagnir Glaurunga
noun. slayer of Glaurung
dag- (“slay”) + (n-)dîr (“man, adult male”, here: “doer”) + Glaurung (dragon-name) + a (Doriathrin genitive ending) #The mutation of dîr to nir might be explained by the Doriathrin origin of the name.
dagnir an glaurung
slayer of Glaurung
túrin turambar dagnir glaurunga
Túrin Turambar, Glaurung’s Bane
dagnir
Dagnir
The Sindarin name Dagnir means "slayer" (or "bane") from dag + (n)dîr, cf. Dagnir Glaurunga "'Glaurung's Bane".
dagnir
bane
(= killer) dagnir (i nagnir, o ndagnir), no distinct pl. form except with article (i ndagnir), coll. pl. dagniriath
dagnir
bane
(i nagnir, o ndagnir), no distinct pl. form except with article (i ndagnir), coll. pl. dagniriath
One of the twelve companions of Barahir (S/155). His name seems to be the noun dagnir “slayer” used as a name.
Conceptual Development: In Silmarillion drafts from the 1930s, this character was first named N. Dengar, soon changed to N. Dagnir (SM/319).