Petty Officer keeps burning picture (5)
I believe the answer is:
photo
'picture' is the definition.
(a photograph)
'petty officer keeps burning' is the wordplay.
'petty officer' becomes 'po' (naval abbreviation).
'keeps' is an insertion indicator.
'burning' becomes 'hot' (similar in meaning).
'po' going around 'hot' is 'PHOTO'.
(Other definitions for photo that I've seen before include "Camera image" , "Picture (abbr)" , "Snap (abbrev.)" , "Pic (abbr)" , "Camera picture" .)