Bladder is a term used to describe an organ in the body that stores urine. There are several synonyms for the term bladder that can be used in different contexts to describe this organ. Some commonly used synonyms for bladder include cyst, vesicle, sac, bladder bag, reservoir, and flexure. These words are often used in medical terminology to describe the bladder organ and its functions. Additionally, some slang terms for bladder include pee bag, pisser, and urine holder. Regardless of the term used, the bladder plays an essential role in the body, and any issues with its function can lead to significant health concerns.