What term best describes an appliance that leaks water continuously while in use?

The term that best describes an appliance that continuously leaks water while in use is "Active Leak." This terminology indicates that the leak is occurring in real-time and is directly associated with the operation or functionality of the appliance. An active leak often suggests an immediate problem that needs to be addressed, as it can lead to more serious issues such as water damage, mold growth, or appliance malfunction.

When considering other terms, "Passive Leak" might imply a leak that happens without active use or can go unnoticed for a period. "Seasonal Leak" suggests that the leakage occurs only during certain times of the year, which does not apply to a constant leak during the appliance's operation. "Negligent Leak" implies a failure to fix an existing leak due to carelessness, rather than describing the state of an ongoing leak itself. Thus, "Active Leak" most accurately conveys the urgency and ongoing nature of the situation.