GO:0014846:   esophagus smooth muscle contraction
A process in which force is generated within smooth muscle tissue, resulting in a change in muscle geometry. This process occurs in the esophagus. Force generation involves a chemo-mechanical energy conversion step that is carried out by the actin/myosin complex activity, which generates force through ATP hydrolysis. The esophagus is the muscular membranous segment between the pharynx and the stomach in the upper gastrointestinal tract.