Foreign seaman - an awful rascal (6)
I believe the answer is:
lascar
'foreign seaman' is the definition.
'lascar' can be an answer for 'seaman' (I've seen this before). I'm unsure of the 'foreign' bit.
'an awful rascal' is the wordplay.
'an awful' indicates anagramming the letters.
'rascal' is an anagram of 'LASCAR'.
Can you help me to learn more?
(Other definitions for lascar that I've seen before include "The East Indian sailor is a rascal" , "Kind of foreign sailor - quite a rascal" , "Asian sailor" , "Indiaman Jack" , "Eastern sailor" .)