Face that shows how old Violet is! (6)
I believe the answer is:
visage
'face' is the definition.
(I know that visage is a type of face)
'how old violet is' is the wordplay.
I cannot really see how this works, but
'violet' could be 'vi' and 'vi' is found in the answer.
'how old' could be 'age' (I've seen this before) and 'age' is found in the answer.
A single letter 's' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'that shows' acts as a link.
Can you help me to learn more?
(Other definitions for visage that I've seen before include "A person's face, countenance" , "Mug" , "Face, aspect" , "Clock" .)