blad ‧ der /ˈblædə $ -ər/ BrE AmE noun [countable]
[ Language: Old English ; Origin: blædre ]
1 . the organ in your body that holds ↑ urine (=waste liquid) until it is passed out of your body
2 . a bag of skin, leather, or rubber, for example inside a football, that can be filled with air or liquid
⇨ ↑ gall bladder