air sac

English Thesaurus

1. any of the membranous air-filled extensions of the lungs of birds (noun.animal)

hypernym	:	sac,
definition	:	a structure resembling a bag in an animal (noun.body)

part meronym	:	bird,
definition	:	warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings (noun.animal)

2. any of the thin-walled extensions of the tracheae of insects (noun.animal)

hypernym	:	sac,
definition	:	a structure resembling a bag in an animal (noun.body)

part meronym	:	insect,
definition	:	small air-breathing arthropod (noun.animal)

3. a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways (noun.body)

hypernym	:	sac,
definition	:	a structure resembling a bag in an animal (noun.body)

part meronym	:	lung,
definition	:	either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood (noun.body)

derivation	:	alveolate, cavitied, faveolate, honeycombed, pitted,
definition	:	pitted with cell-like cavities (as a honeycomb) (adj.all)

derivation	:	alveolate, cavitied, faveolate, honeycombed, pitted,
definition	:	pitted with cell-like cavities (as a honeycomb) (adj.all)