Type of overcoat (6)
I believe the answer is:
'type of overcoat' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for raglan that I've seen before include "Type of 12" , "coat with unique sleeves" , "Kind of sleeve that continues to the neck" , "A lord, a type of sleeve and a Dublin road made famous by Patrick Kavanagh" , "Type of sleeve or overcoat" .)