Seaman stole this empty wagon (9)
I believe the answer is:
boatswain
'seaman' is the definition.
(boatswain is a kind of seaman)
'stole this empty wagon' is the wordplay.
'stole' becomes 'boa' (both can mean a type of scarf).
'empty' says to hollow out the word (remove centre letters).
'wagon' becomes 'wain' (wain is a kind of wagon).
'this' with its middle removed is 'ts'.
'boa'+'ts'+'wain'='BOATSWAIN'
(Other definitions for boatswain that I've seen before include "Seaman" , "I'm chaired to work" , "who has a pipe with a mate?" , "Merchant ship's petty officer" , "In brief, he's a bosun" .)