Stop dishevelled miner entering gallery (9)
I believe the answer is:
terminate
'stop' is the definition.
('terminate' can be a synonym of 'stop')
'dishevelled miner entering gallery' is the wordplay.
'dishevelled' indicates anagramming the letters.
'entering' means one lot of letters goes inside another.
'gallery' becomes 'tate' (I've seen this before).
'miner' is an anagram of 'ermin'.
'ermin' going within 'tate' is 'TERMINATE'.
(Other definitions for terminate that I've seen before include "Stop" , "Close" , "Cut short" , "Put an end to, discontinue" , "Kill off" .)