Definition of "Flutter" :

noun: the act of moving back and forth

noun: the motion made by flapping up and down

noun: a disorderly outburst or tumult

noun: abnormally rapid beating of the auricles of the heart (especially in a regular rhythm); can result in heart block

verb: wink briefly

verb: move back and forth very rapidly

verb: beat rapidly

verb: move along rapidly and lightly; skim or dart

verb: flap the wings rapidly or fly with flapping movements

"The seagulls fluttered overhead."