The fuzzy feeling you get when you like someone A LOT, or when you think something is extraordinarely cute.
Ex 1.
Jaicee: AHHH!!! that cute guy just hugged me!
Lily: Oh my god! Hehehe do you have the tummyflies?
Jaicee: Yes! Dude i can feel them flying around in my tummy.

Ex 2.
Lily: Hehehe i just got the cutest kitten, everytime i see his face i get the tummyflies from its adorableness,
Jaicee: Awwwww.
by Lily Girl October 5, 2009
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