Definition
An aircraft equipped with landing gear that allows it to operate from both water and conventional land surfaces. An amphibian typically combines a hull or floats for water operations with retractable wheels for landings on runways or other prepared surfaces.
Plain English
An aircraft that can take off and land on either water or a runway, because it has both a boat-like hull or floats and wheels that can be lowered or retracted as needed.
Context Anchor
Seen in seaplane, float-equipped aircraft, and landing gear discussions, especially when checking whether the aircraft is set up for land or water operation.
Derivation
From the Greek 'amphi' meaning 'both' and 'bios' meaning 'life' — referring originally to creatures (like frogs) that live both on land and in water. The aviation term carries the same idea: an aircraft at home in two environments.
Why Pilots Care
Operating an amphibian requires confirming gear position before every landing. Wheels down on water or wheels up on a runway can be catastrophic, so amphibian pilots use rigorous gear-check procedures specific to the surface they are landing on.
Intuition Check
Do not read amphibian here as an animal like a frog. In aviation, it means an aircraft able to operate from both land and water.
Example Sentence 1
The mechanic inspected the amphibian's retractable wheels and float structure before signing off the annual.
Example Sentence 2
Training for amphibian operations includes both runway takeoffs and water landings.