τεττιγόνιον
From LSJ
Ἓν οἶδα, ὅτι οὐδὲν οἶδα → I know only one thing, that I know nothing | all I know is that I know nothing.
English (LSJ)
τό,
A a small and voiceless kind of τέττιξ, a leaf-hopper or cicadelle, Arist.HA532b17; fem. pl. tettigoniae, Plin.HN11.92; prob. everywhere f.l. for τιτιγόνιον (q.v.).