Ready to support street band (6)
I believe the answer is:
stripe
'band' is the definition.
('stripe' can be a synonym of 'band')
'ready to support street' is the wordplay.
'ready' becomes 'ripe' ('ripe' can be similar in meaning to 'ready'**).
'to support' means one lot of letters go next to another.
'street' becomes 'st'.
'ripe' after 'st' is 'STRIPE'.
(Other definitions for stripe that I've seen before include "bar" , "Line of different colour - indicator of rank" , "Narrow band of colour" , "Chevron; band" , "Thin band of colour" .)