backpressure noun2 •Pressure that is opposed to the desired flow of a fluid (through a duct).If the back pressure is decreased (p_b) an external expansion occurs, but the duct flow is unchanged. If the back pressure is increased, shocks appear external to the duct (p_c). — 1999 •The buildup of unprocessed data due to a bottleneck; a technique to control the flow of data between producers and consumers.Samsara has tuneables to ensure that back-pressure can be applied so that consumers can process data at the rate they are comfortable with. — 2018 formsbackpressures