διαψιθυρίζω
From LSJ
λίγεια μινύρεται θαμίζουσα μάλιστ' ἀηδών → the sweet-voiced nightingale mourns constantly, the sweet-voiced nightingale most loves to warble
English (LSJ)
A whisper, πρὸς τὸ οὖς προσπίπτων δ. Thphr.Char.2.10. II whisper among themselves, LXXSi.12.18, Plb.15.26.8, Luc. Gall.25.