What condition is characterized by an infection of the bladder?

Cystitis is the correct term for an infection of the bladder. It is commonly associated with urinary tract infections (UTIs) and leads to symptoms such as frequent urge to urinate, pain during urination, and lower abdominal discomfort. The condition arises when bacteria enter the bladder, causing inflammation and symptoms indicative of an infection.

Vesicitis describes inflammation of the bladder, but it is not exclusively used to indicate an infection; it may also refer to non-infectious causes. Balanitis refers to inflammation of the glans (the tip of the penis), typically not related to bladder infections. Urethritis is an inflammation of the urethra, often resulting from infection but specific to that portion of the urinary tract, not the bladder itself. Therefore, cystitis specifically denotes a bladder infection, making it the most accurate answer to the question.