from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A machine shaped like an aircraft that is held aloft and propelled by wing movements.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An aircraft that generates lift through the flapping of its wings.
from The Century Dictionary and Cyclopedia
- n. A flying-machine in which an attempt is made to imitate the oscillatory movement of the wings of a bird.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. heavier-than-air craft that is propelled by the flapping of wings
From ornitho- + -pter. (Wiktionary)