from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A convertiplane that can take off and land vertically.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- vertical takeoff and landing: A description of a fixed-wing aircraft that is capable of ascending into the air straight up as opposed to needing to accelerate horizontally first.
v(ertical) t(ake)o(ff and) l(anding).(American Heritage® Dictionary of the English Language, Fourth Edition)