Close door at the end, blocking various aisles (7)
I believe the answer is:
airless
'close' is the definition.
('airless' can be a synonym of 'close')
'door at the end blocking various aisles' is the wordplay.
'at the end' says to take the final letters.
'blocking' means one lot of letters goes inside another.
'various' is an anagram indicator.
The last letter of 'door' is 'r'.
'aisles' anagrammed gives 'ailess'.
'r' put within 'ailess' is 'AIRLESS'.
(Other definitions for airless that I've seen before include "Very stuffy" , "Still" , "Close" , "not a breath of wind" , "Lacking ventilation" .)