Osteopath loses seat and it's captured for posterity by the cameraman (5)
I believe the answer is:
photo
'osteopath' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for photo that I've seen before include "This race finish is very close" , "Snap, picture" , "Still" , "Snap (abbrev.)" , "Snap, pic" .)