Member of tribe settling in Toulouse - see one leave aboard this at sea (8)
I believe the answer is:
visigoth
'member of tribe' is the definition.
(I've seen this before)
'settling in toulouse see one leave aboard this at sea' is the wordplay.
'settling in toulouse see' becomes 'vi' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'one leave' becomes 'go'.
'aboard' is an insertion indicator.
'at sea' indicates anagramming the letters.
'this' is an anagram of 'sith'.
'go' inserted into 'sith' is 'sigoth'.
'vi'+'sigoth'='VISIGOTH'
Can you help me to learn more?
(Other definitions for visigoth that I've seen before include "he had a smashing time in Rome" , "Old European" , "Alaric, eg, who conquered Rome" , "Spanish settler" , "One of those who sacked Rome in 410" .)