Tiltrotor 

A tiltrotor is an aircraft which utilizes a pair or more of powered rotors (sometimes called proprotors) mounted on rotating shafts or nacelles at the end of a fixed wing for lift and propulsion, and combines the vertical lift capability of a helicopter with the speed and range of a conventional fixed-wing aircraft. Models include the V-22, XV-15 and Bell 609

Tiltrotors are the future of military and civilian flight.

Tiltrotor by NASAguy June 22, 2010

tilt rotor 

A turboprop aircraft that is a hybrid between a plane and helicopter.

The USMC's MV-22 Osprey, and a widely-used form of transportation used by Section 9 in the anime series, "Ghost in the Shell: Stand Alone Complex" are two examples of a tilt rotor.

tilt rotor by tank286 March 26, 2010