Diffraction

n. process of breaking up or bending waves (especially light or sound waves)

Diffraction refers to various phenomena associated with wave propagation, such as the bending, spreading and interference of waves passing by an object or aperture that disrupts the wave. It occurs with any type of wave, including sound waves, water waves, electromagnetic waves such as visible light, x-rays and radio waves. Diffraction also occurs with matter – according to the principles of quantum mechanics, any physical object has wave-like properties. While diffraction always occurs, its effects are generally most noticeable for waves where the wavelength is on the order of the feature size of the diffracting objects or apertures. The complex patterns in the intensity of a diffracted wave are a result of interference between different parts of a wave that traveled to the observer by different paths.
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Noun
1. when light passes sharp edges or goes through narrow slits the rays are deflected and produce fringes of light and dark bands
(hypernym) optical phenomenon
(hyponym) X-ray diffraction
(derivation) diffract

n. diffraction, process of breaking up or bending waves (especially light or sound waves)

(n.)
The deflection and decomposition of light in passing by the edges of opaque bodies or through narrow slits, causing the appearance of parallel bands or fringes of prismatic colors, as by the action of a grating of fine lines or bars.