Pictures one playing games (6)
I believe the answer is:
images
'pictures' is the definition.
('image' can be a synonym of 'picture')
'one playing games' is the wordplay.
'one' becomes 'i' (Roman numeral).
'playing' indicates an anagram.
'games' anagrammed gives 'mages'.
'i'+'mages'='IMAGES'
(Other definitions for images that I've seen before include "Reflections in a mirror" , "Likenesses or effigies" , "Pictures; metaphors" , "Pictures or photos" , "Reflections in mirrors" .)