Send off -- case of damage and small repair (8)
'send off' is the definition.
('despatch' can be a synonym of 'send off')
'case of damage and small repair' is the wordplay.
'case of' says to hollow out the word (remove centre letters) (outsides of).
'and' means one lot of letters go next to another.
'small' becomes 's' (abbreviation - e.g. clothes size).
'repair' becomes 'patch' (patching is a kind of repairing**).
'damage' with its middle taken out is 'de'.
(Other definitions for despatch that I've seen before include "Bulletin", "Send out of cash dept", "expedition", "Give send-off", "Send off, kill".)