An NG tube is a flexible tube made of rubber or plastic and has bidirectional potential. A nasogastric tube can thus be used to remove the contents of the stomach including air (to decompress the stomach) and small solid objects and fluid (e.g., to evacuate poison from the stomach). A nasogastric tube can also be used to instill liquids into the stomach (e.g., to feed the person).
The word "nasogastric" is a hybrid -- part Latin, part Greek. "Naso-" is a prefix that has to do with the nose and comes from the Latin "nasus" for nose or snout. "Gastric" comes from the Greek "gaster" meaning the paunch or belly. The term "nasogastric" was coined in 1942.