The name Hieronymus is a boy's name of German origin meaning "sacred name". Hieronymus and discussed in our forums with posts like "Quick Question Thread?!".
From the experts:
This cognate of Jerome (of all things), familiar via the Dutch painter of fantastical scenes, H. Bosch, would appeal only to the most audacious, intrepid, attention-seeking baby namer. It is, however, still used in Germany, especially in Catholic Bavaria and in the north German Rhineland.