1 [intransitive and transitive]HBI
if a bird or insect flutters, or if it flutters its wings, it flies by moving its wings lightly up and down:
A small bird fluttered past the window.
to make small gentle movements in the air:
Dead leaves fluttered slowly to the ground.
The flag fluttered in the light breeze.
if your heart or your stomach flutters, you feel very excited or nervous
if your eyelids flutter, they move slightly when you are asleep:
Her eyelids fluttered but did not open.
if a woman flutters her eyelashes at a man, she looks at him and moves her eyes to make herself attractive to him