fluttering

1. Rapid back-and-forth or up-and-down waving or oscillation of, e.g. wings or a vibrating engine; the condition of engaging in such an action.

   I was entranced by the colorful fluttering of the butterfly's wings.

   The valve's fluttering is a problem, you have to find where it comes from.

2. The action of atrial flutter, in which the upper chambers of the heart beat too rapidly.

   Treatment will reduce the fluttering in your heart.

3. A feeling of internal shifting, as with indigestion, nervous flutters, etc.

   The fluttering in her belly reminded her that her child was coming one day soon.

   He felt a fluttering of discontent, but he said nothing.

regular