[lahy-ter-th uh n-air]
- (of an aircraft) weighing less than the air it displaces, hence obtaining lift from aerostatic buoyancy.
- of or relating to lighter-than-air craft.
Origin of lighter-than-air
First recorded in 1900–05
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
lighter than air
- having a lower density than that of air
- of or relating to an aircraft, such as a balloon or airship, that depends on buoyancy for support in the air