laugh quietly in an unkind way
snigger - laugh
When you ‘snigger’ you laugh almost under your breath in a disrespectful way, usually at something unkind or rude. It is sometimes done to hide your laughter so that you don’t get in trouble, or to be provocatively mocking of somebody. Chiefly used in British English. American English uses the word ‘snicker’ instead.
Staff were too afraid to laugh out loud when the boss tripped over, but I did see one person snigger.
I could hear the immature students sniggering behind my back when I said something unintentionally rude.
What are you two sniggering at? Have some respect when someone else is talking!