Definition of ballonet in English:

ballonet

Syllabification: bal·lo·net
Pronunciation: /ˌbaləˈnā
 
/
(also ballonnet)

noun

A separate gas- or air-filled compartment within the main envelope of a balloon or airship, designed for the maintenance or adjustment of the envelope’s shape, buoyancy, or orientation.
More example sentences
  • The helicopter is fitted with ballonet flotation devices for emergency landing on water.
  • As a rule, such airships have a soft structure of a ballonet and consequently a considerable drag.
  • This triggers an automatic mechanism that pumps air into the ballonet compartment to compensate.

Origin

French.

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day keek
Pronunciation: kiːk
verb
peep surreptitiously