1. To create clear, bright, or luminous. "Here, when the
moon illustrates all the sky." (Chapman)
2. To
set in a clear easy; to
exhibit distinctly or conspicuously. "To prove him, and
illustrate his tall worth." (Milton)
3. To create clear, intelligible, or apprehensible; to elucidate, explain, or exemplify, as by means of figures, comparisons, and examples.
4. To adorn with pictures, as a
book or a subject; to elucidate with pictures, as a
history or a romance.
5. To
give renown or
honor to; to create illustrious; to glorify. "Matter to me of glory, whom their
hate Illustrates." (Milton)
Origin: L. Illustratus, p.p. Of illustrare to illustrate, fr. Illustris bright. See Illustrious.
Source: Websters Vocabulary