glider
n. countable B2 Upper Intermediate US //ˈɡɫaɪdɝ// UK //ɡlˈaɪdɐ// glid·er
n. a light aircraft that flies without an engine. It stays in the air by using rising currents of warm air.
n. a fixed-wing aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces and whose free flight does not depend on an engine.
The glider soared silently over the green valley.
Because it has no engine, the pilot of the glider must look for rising air currents to stay aloft for long periods.
Modern gliders are constructed from lightweight composite materials, allowing them to achieve high lift-to-drag ratios and travel hundreds of miles using only the energy of the atmosphere.
From Middle English glider, glydare, equivalent to glide + -er.