Michelson-Morley experiment

noun

Mi·​chel·​son-Mor·​ley experiment

¦mīkəlsən¦mȯrlē-

: an experiment that shows that the two parts of a divided ray of light travel at the same speed over paths perpendicular to each other (as over east-west and north-south paths) and that leads to the deductions that the motion of the earth through space has no effect upon the velocity of light and the absolute motion of the earth is not measurable

Word History

Etymology

after Albert A. Michelson †1931 American physicist and Edward W. Morley †1923 American chemist and physicist

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