Subtle manoeuvring on railway that’s windy (8)
I believe the answer is:
blustery
'windy' is the definition.
(thesaurus)
'subtle manoeuvring on railway' is the wordplay.
'manoeuvring' indicates an anagram.
'on' is a charade indicator (letters next to each other).
'railway' becomes 'ry' (abbreviation for railway).
'subtle' with letters rearranged gives 'bluste'.
'bluste'+'ry'='BLUSTERY'
'that's' acts as a link.
(Other definitions for blustery that I've seen before include "Sly brute (anag)" , "Blowing in fits and starts" , "Spasmodically windy" , "Boastful" , "Squally" .)