Stop to have a breather around end of year (6)
I believe the answer is:
arrest
'stop' is the definition.
(I know that arrest is a kind of stop)
'a breather around end of year' is the wordplay.
'breather' becomes 'rest' (a breather is a break or rest).
'around' indicates putting letters inside.
'end of' indicates one should take the final letters.
The last letter of 'year' is 'r'.
'rest' going around 'r' is 'rrest'.
'a'+'rrest'='ARREST'
'to have' is the link.
(Other definitions for arrest that I've seen before include "Nab" , "Collar" , "Take into legal custody" , "Apprehend; detain" , "apprehend a law-breaker" .)