Taking permission day before stir (5)
I believe the answer is:
evoke
'stir' is the definition.
(thesaurus)
'taking permission day before' is the wordplay.
'taking' means one lot of letters goes inside another.
'permission' becomes 'ok' (what is said to give permission).
'day before' becomes 'eve' (I've seen this before).
'ok' inserted into 'eve' is 'EVOKE'.
(Other definitions for evoke that I've seen before include "Call up as from memory" , "Recall" , "Awaken memories in the mind" , "Conjure up" , "Kindle (memory)" .)