boundary layer

American  

noun

Physics.

1. the portion of a fluid flowing past a body that is in the immediate vicinity of the body and that has a reduced flow due to the forces of adhesion and viscosity.

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boundary layer British  

noun

1. the layer of fluid closest to the surface of a solid past which the fluid flows: it has a lower rate of flow than the bulk of the fluid because of its adhesion to the solid

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Etymology

Origin of boundary layer

First recorded in 1920–25

Example Sentences

To examine chemical activity in the Arctic boundary layer, the research team collected air samples over snow-covered and newly frozen sea ice in the Beaufort and Chukchi Seas.

From Science Daily

Collected by gliders, floats and drifters, these instruments provide valuable information about the most turbulent region of the hurricane environment, called the boundary layer, where the air meets the ocean.

From BBC

"The particles adopt a certain orientation very early on, i.e. in the boundary layer between the water and the sediment. This alignment increases further within the first few millimetres of sediment," explains Kühn.

From Science Daily

In atmospheric science, the boundary layer of the atmosphere is the region closest to the Earth's surface.

From Science Daily

"The structure they are researching, which engineers call the atmospheric boundary layer, monitors how the wind's speed, temperature and pressure varies with altitude."

From Science Daily