WordNet
n. a flight that begins and ends in the same country [ant: international flight]
Wikipedia
A domestic flight is a form of commercial flight within civil aviation where the departure and the arrival take place in the same country.
Airports serving domestic flights only are known as domestic airports.
Domestic flights are frequently, but not necessarily, non-stop flights.
Domestic flights are generally cheaper than most International flights. Some international flights may be cheaper than domestic ones due to the short distance between the pair of cities in different countries.
Usage examples of "domestic flight".
She would then take a domestic flight to Paris and she would find him.
This time he'd flown to Mexico, driven across the border, then taken a domestic flight into D.
He was again directed to the airlines, this time for a domestic flight.