Hot seat may shatter the unadventurous (4-2-4)
I believe the answer is:
stay-at-home
'the unadventurous' is the definition.
(I've seen this before)
'hot seat may shatter' is the wordplay.
'shatter' indicates anagramming the letters (I've seen 'shattered' mean this).
'hot'+'seat'+'may'='hotseatmay'
'hotseatmay' with letters rearranged gives 'STAY-AT-HOME'.
(Other definitions for stay-at-home that I've seen before include "Unadventurous in travel" , "Person disinclined to travel" , "Don't go out" , "One not given to travel" .)