αἴφνης

Adv.
A. suddenly, E. IA 1581, Hp. Int. 39 (αἰφνηδίς, Hdn. Gr.1.512; αἰτι‐δόν, Id. Epim. 270). (Prob. cognate with αἶψα rather than with ἄφαρ, ἄφνω).
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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