Is unable to go to Glasgow for shelter (6)
I believe the answer is:
canopy
'for shelter' is the definition.
(canopy is a kind of shelter)
'is unable to go to glasgow' is the wordplay.
I cannot quite understand how this works, but
'unable to' could be 'no' (I've seen this in other clues) and 'no' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for canopy that I've seen before include "Overhanging cover" , "Covering serving as shelter" , "Covering over four-poster, etc" , "Ornamental covering" , "Uppermost branches of forest trees" .)