Leonardo da Vinci’s invention using flapping wings inspired by birds and bats was an ornithopter.
An ornithopter is an aircraft designed to fly by moving its wings up and down, rather than by using fixed wings and a propeller. Leonardo studied bird flight closely and filled notebooks with observations about wing motion, balance, and air resistance.
His proposed machines included frames, wings, and mechanical systems intended to transfer human movement into wing beats. None achieved powered flight, because a human pilot could not produce the necessary energy through the proposed mechanisms.
The term is broader than Leonardo’s work: inventors before and after him also explored flapping-wing aircraft. Leonardo’s contribution was his unusually detailed study of anatomy and aerodynamics, which made his designs more systematic than many earlier flying-machine concepts.