French river or small German article (5)
I believe the answer is:
seine
'french river' is the definition.
(I've seen this in another clue)
'small german article' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'german article' becomes 'eine' (indefinite article in German).
's'+'eine'='SEINE'
'or' is the link.
(Other definitions for seine that I've seen before include "French river -- type of fishing net" , "Paris river" , "Parisian river" , "Paris's river" , "Second longest river in France" .)