What is the definition or description of: intubation?

Airway Maintenance : It is the insertion of a tube into the trachea to maintain a secure airway. This is essential for safe general anaesthesia.

Breathing Tube : In general, anesthesiologists use this term to describe the placement of a breathing to into the windpipe (under general anesthesia) to assure that the airway is safely (1) separated from anything other than oxygen and anesthesia and that (2) only the amount of anesthesia required, and nothing more, is delivered to one's breathing system.

Intubation: Means placing a tube to create a conduit. In general anesthesia, the airway is typically intubated to provide a conduit for air to pass in and out of the lungs. If the tube is passed through the vocal cords and its balloon cuff is inflated, it will also protect your lungs from aspiration of gastric contents.