0 French for 'in passing': if you say something en passant, you mention it quickly while talking about something else: --
I have to say en passant that the contributions to this debate so far have been incredibly stimulating.
To say en passant that bus services had been in decline is palpably untrue.
I should say en passant that monetary sovereignty cannot be claimed on borrowed money.
I notice, en passant, that the treaty deficit column is headed "treaty commitments".
I merely mention that en passant, but it is rather extraordinary.
That shows, en passant, how time brings change.
However, that is mentioned rather en passant.
I made my comment en passant, as they say.
