Bosch, Hieronymus Syllabification: (Bosch, Hieronymus)Pronunciation: /bäSH, bôSH/Definition of Bosch, Hieronymus (circa 1450–1516), Dutch painter. His highly detailed works are typically crowded with half-human, half-animal creatures and grotesque demons in settings symbolic of sin and folly. Bosch, Hieronymus in other Oxford dictionaries Definition of Bosch, Hieronymus in the British & World English dictionary