What is the definition or description of: heartburn?

Agita: When acid and peptic juices reflux into the esophagus, one might have the sensation of burning or pain under the breast bone. It can radiate up to the throat and down to the region of the solar plexus. Some may describe it as bad 'indigestion' and others may feel like they are having a heart attack.

Heartburn: Heartburn occurs when acid from the stomach refluxs or splashes up into the esophagus (and sometimes the mouth or throat). Sx's: burning pain that may be felt in chest, abdomen or throat that may last minutes to hours. Pain can ^ right after eating, lying down or bending over. It may feel like food is stuck in the throat or chest & swallowing may be more difficult. Bitter/ sour/ hot taste >