Sailor Brown checked pattern (6)
I believe the answer is:
tartan
'checked pattern' is the definition.
(I've seen this before)
'sailor brown' is the wordplay.
'sailor' becomes 'tar' (slang term for a sailor).
'brown' becomes 'tan' (tan is a kind of brown).
'tar'+'tan'='TARTAN'
(Other definitions for tartan that I've seen before include "Scots patterned cloth" , "chequered cloth" , "Distinctive cloth pattern of a Highlands clan" , "Cloth with a plaid design" , "Scots material" .)