The anterior edge of a gill slit is motile, moving outward to allow water to exit, but closing to prevent reverse flow.

His enthusiasm is obvious as he speaks of the "reverse flow of technology coming from the third world to the first world."

A good example of this 'reverse flow' comes from certain developments in the semiconductor industry.

This includes all activities of the forward and reverse flows.

This will cause reverse flow into the intake port until pressure in the cylinder falls below the ports pressure).

Tidal fluctuations cause reverse flow on the lower slough.

In addition, even if we shut down the pumping stations, we would be faced with reverse flows from the various megascrapers.

Following the end of forward conduction in a p-n type diode, a reverse current flows for a short time.

Salt water enters from the North Sea through straits when the sea level is high enough to allow reverse flow over the sill.

A pair of non-return check valves prevent reverse flow of the fluid.