Jog in strictest rotation (4)
I believe the answer is:
trot
'jog' is the definition.
(I know that jog can be written as trot)
'in strictest rotation' is the wordplay.
'in' indicates a hidden word.
'TROT' is hidden within 'strictest rotation'.
(Other definitions for trot that I've seen before include "Jog along" , "Run with short steps" , "Move at brisk pace" , "equestrians sometimes associate with rising" , "Clip (horse)" .)