noun
1. : a bag for holding water ; especially : one designed to keep water cool for drinking by evaporation through a slightly porous surface
2.
a. : the reticulum of a camel or a closely related animal
b. : the fetal membranes enclosing the amniotic fluid — used especially of domestic animals
c. : a pouch filled with serous fluid ; also : any of several abnormalities of domestic animals characterized by such a pouch