Plain English Meaning
An airplane with more than one engine.
Full Definition
An airplane powered by two or more engines. In FAA usage, it refers to fixed-wing aircraft with more than one powerplant, which introduces specific handling considerations during normal operations and especially when one engine fails, including asymmetric thrust and altered stall behavior.
Context Anchor
Seen in training, operating procedures, and handbook discussions for airplanes that have two or more engines.
Derivation
Multi-' comes from Latin multus, meaning 'many.' So a multiengine airplane is simply one with many (more than one) engines.
Why Pilots Care
Multiengine airplanes behave differently from single-engine airplanes when one engine fails. The remaining engine produces on one side only, which yaws and rolls the airplane and changes stall and . flying requires its own training and a separate .