to give someone butterflies
to make someone feel nervous or excited, often in a romantic way · to cause a fluttery feeling in someone's stomach
What's the situation?
When someone or something makes you feel excited or nervous, usually in a good way, you might get 'butterflies in your stomach.' But if *you* are the cause of that fluttery feeling in *someone else*, you 'give them butterflies'! It's often used in romantic contexts, like a new crush making you feel giddy! 😍