Faint winds waft, offering no initial protection against cold weather (10)
I believe the answer is:
antifreeze
'faint winds waft offering no initial protection' is the definition.
I can't tell whether this defines the answer.
'against cold weather' is the wordplay.
'against' becomes 'anti' (prefix meaning against).
'cold weather' becomes 'freeze' (freeze is a kind of cold weather).
'anti'+'freeze'='ANTIFREEZE'
Can you help me to learn more?
(Other definitions for antifreeze that I've seen before include "Glycol for car radiators" , "Liquid added to car radiator" , "Winter radiator additive" , "which prevents ice damage" , "Ethylene glycol" .)