diffraction has definitions from the field of physics
1
[ noun ] (physics) when light passes sharp edges or goes through narrow slits the rays are deflected and produce fringes of light and dark bands

Used in print

(Francis J. Johnston and John E. Willard, "The...)

The photochemical_reaction cells consisted_of 10 mm. i.d. Pyrex tubing , 5.5 cm. long , diffraction effects being minimized by the fact that the light passed_through only liquid glass interfaces and not gas glass interfaces .

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