Rule out (7)
'rule out' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for exclude that I've seen before include "Keep out" , "Bar from entrance" , "Ostracise" , "Omit or shut out" , "Bar, ban" .)
'rule out' is the definition.
(synonyms)
This is all the clue.
(Other definitions for preclude that I've seen before include "Obviate, prevent" , "Make impossible" , "Debar" , "Prevent, prohibit" , "Prevent, forestall the possibility of" .)