Côte d’Ivoire
montrer les dents
“to show the teeth”
Meaning
to grin broadly
Elsewhere
rire à pleines dents
Explanation
Do this in France and you are squaring up for a fight, baring your teeth the way an animal does. In Côte d'Ivoire and Chad it means grinning broadly, and it is not usually meant kindly.
Example
Arrête de montrer les dents, ce n’est pas drôle.
Stop grinning like that, it isn't funny.
Origin
Origin uncertain.
Where
Côte d’Ivoire
Chad