Picture taken lightly? (5)
I believe the answer is:
photo
'picture' is the definition.
(a photograph)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for photo that I've seen before include "In brief, a snapshot" , "Snap, exposure, in short" , "Pic (abbr)" , "Picture, in short" , "Snap - shot" .)