Saw some Canada geese (5)
I believe the answer is:
adage
'saw' is the definition.
(saw can mean a proverb or saying)
'some canada geese' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'ADAGE' is hidden in the letters of 'canada geese'.
(Other definitions for adage that I've seen before include "Saying, saw" , "True proverb or saying" , "Axiom" , "Proverb, maxim" , "Saw, proverb" .)