Cane that traitor Brown (6)
I believe the answer is:
rattan
'cane' is the definition.
(I know that rattan is a type of cane)
'traitor brown' is the wordplay.
'traitor' becomes 'rat' (rat can mean a treacherous person).
'brown' becomes 'tan' (tan is a kind of brown).
'rat'+'tan'='RATTAN'
'that' is the link.
(Other definitions for rattan that I've seen before include "Palm tree with long stems used in furniture" , "Furniture-maker" , "Wickerwork material" , "Palm cane used in wickerwork" , "Climbing palm used for wicker and canes" .)