the.com/wind shear

means A sudden change in wind speed or direction over a short distance, which can jolt or destabilize aircraft, especially during takeoff and landing.

from Straightforward compound: 'wind' plus 'shear,' the physics term for forces that cause layers of a substance to slide against each other in opposite directions. Shear in this sense comes from Old English 'sceran,' to cut — the same root behind scissors and shears. Meteorologists borrowed the mechanical image because that's exactly what happens: adjacent layers of air moving at different speeds or directions, cutting against one another like blades. The aviation danger of wind shear became widely studied and named after several crashes in the mid-20th century were traced to it, pushing the term from technical jargon into common safety vocabulary.