Dock worker to deserve rum (9)
I believe the answer is:
stevedore
'dock worker' is the definition.
(synonyms)
'to deserve rum' is the wordplay.
'rum' indicates an anagram (rum can mean strange or unusual).
'to'+'deserve'='todeserve'
'todeserve' is an anagram of 'STEVEDORE'.
(Other definitions for stevedore that I've seen before include "he'll have loads on board" , "one working in docks" , "One loads and unloads ships" , "Dock worker" , "Dock-worker loads and unloads ships" .)