blad·der noun \ˈblad-ər\
: a membranous sac in animals that serves as the receptacle of a liquid or contains gas; especially : urinary bladder
: a vesicle or pouch forming part of an animal body <the bladder of a tapeworm larva>
Seen & Heard
What made you want to look up bladder? Please tell us where you read or heard it (including the quote, if possible).