Medical examination (5-2)
'medical examination' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for check-up that I've seen before include "Medical examination" , "Quick dental visit" .)
'medical examination' is the definition.
(synonyms)
This is all the clue.
(Other definitions for checkup that I've seen before include "An occasional precautionary medical examination" , "Precautionary or routine visit to G.P." , "Quick dental visit" .)