Abbott-Smith Manual Greek Lexicon
πτόησις (G4423)
1 πτόησις , -εως, ἡ ( πτοέω ), [in LXX: Pr 3:25 ( פַּחַד ), Sir 50:4 א 1 , I Mac 3:25 R*;] a fluttering , excitement , caused by any emotion, but esp. by fear, hence, terror : φοβεῖσθαι πτόησιν , to be afraid with (cogn. acc.) or of any terror (v. ICC , in l.): I Pe 3:6 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain