καταθαρρέω
From LSJ
Σκηνὴ πᾶς ὁ βίος καὶ παίγνιον: ἢ μάθε παίζειν, τὴν σπουδὴν μεταθείς, ἢ φέρε τὰς ὀδύνας → All life is a stage and a play: either learn to play laying your gravity aside, or bear with life's pains.
Dutch (Woordenboekgrieks.nl)
κατα-θαρρέω vol vertrouwen zijn, adv. ptc. perf. κατατεθαρρηκότως vol zelfvertrouwen.