... one repeatedly coming back from Canadian adventures (3)
I believe the answer is:
dan
'one repeatedly coming' is the definition.
I can't tell whether this definition defines the answer.
'back from canadian adventures' is the wordplay.
'back' says the letters should be written in reverse.
'from' says the answer is hidden in the clue.
'nad' can be found hidden inside 'canadian adventures'.
'nad' written backwards gives 'DAN'.
(Other definitions for dan that I've seen before include "Dark and damp." , "Level of proficiency in Japanese martial arts" , "Level of proficiency in Japanese combative sport" , "A Desperate cartoon character" , "Level of competence in judo" .)