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[ noun ] the physical coming together of two or more things
Examples "contact with the pier scraped paint from the hull" Used in print (J. F. Vedder, "Micrometeorites", in Francis S. J...)The Poynting-Robertson effect ( Robertson , 1937 ; Wyatt and Whipple , 1950 ) , which is a retardation of the orbital motion of particles by the relativistic aberration of the repulsive_force of the impinging solar_radiation , causes the dust to spiral into the sun in times much shorter than the age of the Earth . (LeRoy Fothergill, "Biological Warfare", in Peter...)The natural anatomical and physiological defensive features of the upper respiratory_tract , such_as the turbinates of the nose and the cilia of the trachea and larger bronchi , are capable of impinging out the larger particles to which we are ordinarily exposed in our daily existence . Very small particles , however , in a size range of 1 to 4 microns in diameter are capable of passing these impinging barriers and entering the alveolar_bed of the lungs . |
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