malin

Ne fais pas le malin ! Tu aurais pu te blesser.

Don't be smug! You could have hurt yourself.

Un petit malin a laissé le lait hors du frigo toute la nuit.

Some wise guy left the milk out of the refrigerator all night.

Tom était un petit malin dans sa jeunesse.

Tom was a clever scamp in his youth.

Ouais, on sait déjà que tu es un gros malin !

Yeah, we already know you're a big guy!