1. provide (a book, newspaper, etc.) with pictures: "the guide is illustrated with full-color photographs"Similardecorateadornornamentembellishaccompanyadd pictures/drawings/sketches toprovide artwork for
Word Originearly 16th century (in the sense ‘illuminate, shed light on’): from Latin illustrat- ‘lit up’, from the verb illustrare, from in- ‘upon’ + lustrare ‘illuminate’.