Quenya 

nehtar

slayer

#nehtar noun "slayer", isolated from Morinehtar "Darkness-slayer" (PM:384, 385). It may be that a verbal stem #nehta- "to slay, kill" can also be isolated from this noun, though the attested form is actually nahta- (a possible example of A/E variation).

nehtar

noun. slayer

An element in Morinehtar “Darkness-slayer”, a name of one of the Blue Wizards (PM/384). It seems to be an agental form of nahta- “to slay”, but the reason why the vowel is e is unclear.