This term can be used to describe the feeling of being in love; when one is feeling speechless or completely in bliss only when they're around the person they love or have feelings for.
You: Everytime I see her, I get butterfly brain bro.
Homie: Bruh what the fuck are you talking about, butterfly what?
You: Butterfly brain nigga, i'm speechless everytime I'm around her.
Homie: How about you stop being a little bitch and go tell her how you feel then?
To be massively forgetful and go off on the greatest tangents. Tangents often lead to embarasssing relatable stories
I have a butterfly brain