flushing

Flushing is the act of causing liquid or gas to flow rapidly through a system to clear, cleanse, or renew it. In plumbing and sanitation, flushing describes both a deliberate purge of a pipe or tank and the operation of a toilet that releases waste through a drain. A flush may involve fresh water or a dedicated flushing fluid and is used to remove sediment, deposits, or contaminants, or to restore normal flow after maintenance.

In domestic toilets, the flush releases water from the tank into the bowl and down the drain, carrying away waste. In pipelines, flushing uses high-velocity fluid to remove debris and sediment from lines. In water systems, flushing hydrants or mains helps clear sediments and maintain water quality, and may be scheduled during maintenance.

Medical flushing refers to a temporary reddening of the skin, usually the face and neck, caused by vasodilation of surface blood vessels. Triggers include heat, emotions, alcohol, spicy foods, niacin, or certain medications. Persisting flushing may indicate an underlying condition such as rosacea or carcinoid syndrome.

In computing and data processing, flushing means forcing buffered data to be written to its destination or to clear a buffer, queue, or cache. Examples include flushing a file stream, a memory cache, or a networking buffer to ensure timely delivery of information.

In environmental science, flushing describes the exchange of fresh and salt water in estuaries or lakes, influencing salinity, contaminants, and ecosystem health. The rate is affected by tides, rainfall, river inflow, and water management practices.