Obstructs (4)
'obstructs' is the definition.
('stymy' can be a synonym of 'obstruct')
This is the entire clue.
'obstructs' is the definition.
(blocking is a kind of obstructing)
This is all the clue.
(Other definitions for blocks that I've seen before include "Three-dimensional shapes with six sides" , "Impedes" , "Prevents the movement of, gets in way" .)
'obstructs' is the definition.
(barring is a kind of obstructing)
This is all the clue.
(Other definitions for bars that I've seen before include "Obstacles" , "Prohibits; pubs" , "Blocks off" , "Drinking holes; prohibits" , "Drinking establishments" .)