laugh up (one's) sleeve

To try to hide that one is laughing at someone else. Ron may seem like a nice guy, but he laughs up his sleeve whenever he's around someone he dislikes. The popular kids laugh up their sleeves every time I walk by—it's so infuriating.

Common Names:

Name	Pronounced	Usage
Yaroslava	yah-rah-SLAH-vah (Russian)	Russian, Ukrainian, Medieval Slavic
Saana	-	Finnish
Elwood	['elwud]
Nikola (1)	-	Serbian, Croatian, Slovene, Bulgarian, Macedonian, Hungarian, Czech, Basque, Medieval Slavic
Cyrilla	-	English (Rare)
Krysia	KRI-shah	Polish