LSJ
Adv., (< περιπτίσσω) in a winnowed, clean style, metaph, of speech, Poll. 6.150 (ante 146).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
adv. part. perf. pass. von περιπτίσσω, entülset.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)