A total gastrectomy is a medical procedure where all of the stomach is surgically removed and a communication between oesophagus (the food pipe) and jejunum (proximal part of small bowel) is established. 

A partial gastrectomy is a medical procedure where part of the stomach (usually lower) is surgically removed and a communication between upper stomach and jejunum (proximal part of small bowel) is established.

It is a medical procedure where the lower part of esophagus and part or whole of the stomach is surgically removed and a communication between mid or lower esophagus and jejunum (proximal part of small bowel) is established. Usually the anastomosis is done inside the chest.