ἀνθυποπτεύω
From LSJ
Τὸ νικᾶν αὐτὸν αὑτὸν πασῶν νικῶν πρώτη τε καὶ ἀρίστη. Τὸ δὲ ἡττᾶσθαι αὐτὸν ὑφ' ἑαυτοῦ πάντων αἴσχιστόν τε ἅμα καὶ κάκιστον. → Τo conquer yourself is the first and best victory of all, while to be conquered by yourself is of all the most shameful as well as evil
English (LSJ)
A suspect mutually, ἀλλήλους D.C.45.8: abs., Aen. Tact.24.11 (cj.):—Pass., ἀνθυποπτεύεται . . πλέον ἕξειν he is met by the suspicion that... Th.3.43.