laugh up your sleeve
US /læf ʌp jʊər sliːv/
UK /læf ʌp jʊər sliːv/
1.
rire sous cape, rire en douce
to be secretly amused about something, often at someone else's expense
:
•
She tried to keep a straight face, but I could tell she was laughing up her sleeve.
Elle a essayé de garder un visage impassible, mais je pouvais dire qu'elle riait sous cape.
•
The politician pretended to be concerned, but everyone knew he was laughing up his sleeve at the public's gullibility.
Le politicien a fait semblant d'être préoccupé, mais tout le monde savait qu'il riait sous cape de la crédulité du public.