Study timekeeper? (5)
I believe the answer is:
watch
I believe this clue is a double definition.
'study' is the first definition.
(I know that watch is a more specific form of check)
'timekeeper?' is the second definition.
(I know that watch is a type of timekeeper)
(Other definitions for watch that I've seen before include "Observe - timepiece" , "Keep under observation" , "Observe - guard" , "View" , "Look at attentively" .)