Meaning of “illustration” - Learner’s Dictionary

illustration

noun uk us /ˌɪləˈstreɪʃən/
PICTURE [ C ]

B2 a picture in a book, magazine, etc:

a full-page colour illustration
EXAMPLE [ C, U ]

an example that explains or proves something:

This is another illustration of the power of the media.

(Definition of “illustration” from the Cambridge Learner’s Dictionary © Cambridge University Press)