Shoot at stoat going round at rear of building (9)
I believe the answer is:
germinate
'shoot' is the definition.
('germinate' can be a synonym of 'shoot')
'at stoat going round at rear of building' is the wordplay.
'stoat' becomes 'ermine' (I've seen this before**).
'going round' is an insertion indicator.
'at' says to put letters next to each other (I've seen this in other clues).
'rear of' suggests the final letters.
The last letter of 'building' is 'g'.
'at' put into 'ermine' is 'erminate'.
'erminate' after 'g' is 'GERMINATE'.
(Other definitions for germinate that I've seen before include "Sprout - develop" , "Put forth shoots, develop and grow" , "(Of seeds) sprout" , "Sprout as in a regiment" , "(Of seed) start to shoot" .)