Liddell-Scott-Jones

ὀλέθριος (olethrios) pernicious ^G:A

ὀλέθριος-ιος, ον,

[Refs 5th c.BC+]; but α, ον [LXX+5th c.BC+]:— destructive, deadly, ὀ. ἦμαρ the day of destruction, [Refs 8th c.BC+] etc.; so μανίη πάγχυ ὀ. Hdt. [prev. cited]; ὀ. μόρος [Refs 4th c.BC+]; ὀλεθρία νύξ [Refs 5th c.BC+], etc.; ψῆφος ὀλεθρία a vote of death, [ὀλέθριοςιον αἰκίζει">Refs 5th c.BC+] fatally, [Refs]:—rare in Prose, as [Refs 5th c.BC+]. adverb -ίως[Refs]

__2 c.genitive, γάμοι Πάριδος ὀλέθριοςιοι φίλων bringing ruin on his friends, [Refs 4th c.BC+]
__3 with dative, as substantive, ψύλλοις ὀλέθριοςιον, name of a fluid, [Refs 3rd c.AD+]
__II of persons, in danger of death, [Refs 5th c.BC+]; lost, undone, [Refs 5th c.BC+]. adverb -ίως, ἔχειν [Refs 2nd c.AD+]
__II.2 rascally, worthless [Refs 2nd c.AD+] codices ὀλεθρ-ιώδης, ες, gloss on{λευγαλέη}, [Refs 5th c.AD+]