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FitzGerald contraction

noun Physics.
  1. the hypothesis that a moving body exhibits a contraction in the direction of motion when its velocity is close to the speed of light.

Origin of FitzGerald contraction

First recorded in 1915–20; named after G. F. FitzGerald
Also called Fitz·Ger·ald-Lo·rentz contrac·tion [fits-jer-uh ld lawr-ents, -lohr-] /fɪtsˈdʒɛr əld ˈlɔr ɛnts, -ˈloʊr-/, Lorentz-FitzGerald contraction, Lorentz contraction, length contraction.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018