Example or illustration (8)
I believe the answer is:
instance
This clue is a double definition.
'example' is the first definition.
(I know that example can be written as instance)
'illustration' is the second definition.
(I know that illustration can be written as instance)
(Other definitions for instance that I've seen before include "Occasion" , "Particular case; cite" , "Example or single occurrence of something" , "Specimen" , "'Example, illustration (8)'" .)