Abbott-Smith Manual Greek Lexicon
ἀπο-κτείνω (G615)
74 ἀπο-κτείνω (also in late forms -κτέννω , Mt 10:28 , a1., LTTr., -κτεννύω , Mk 12:5 , WH), [in LXX for הרג , מוּת ;] to kill : Mt 14:5 , al.; seq. instr. ἐν (q.v.), Eph 2:16 , Re 2:23 , al. Metaph.: Ro 7:11 ; τ. ἔχθραν , Eph 2:16 ; τὸ γράμμα ἀποκτείνει , II Co 3:6 (on the perfective force of this verb, v. M, Pr. , 114).
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain