Greek character forms cuter image (7)
I believe the answer is:
Here is my best explanation:
'image' is the definition.
(picture is a kind of image)
'greek character forms cuter' is the subsidiary indication.
'greek character' becomes 'pi'.
'forms' indicates anagramming the letters.
'cuter' anagrammed gives 'cture'.
(Other definitions for picture that I've seen before include "Depiction", "Drawing", "Painting, drawing or film", "Visual representation", "Imagine; film", "Portrait; film", "One can paint a thousand words, it's said", "Representation", "Hanging wall adornment" and "A visual representation".)