Definition of Michelson–Morley experiment in US English:

Michelson–Morley experiment

proper noun

  • An experiment performed in 1887 which attempted to measure the relative motion of the earth and the ether by measuring the speed of light in directions parallel and perpendicular to the earth's motion. The result disproved the existence of the ether, which contradicted Newtonian physics but was explained by Einstein's special theory of relativity.


Named after A. A. Michelson (see Michelson, Albert Abraham) and E. W. Morley (see Morley, Edward Williams).


Michelson–Morley experiment

/ˌmīkəlsənˈmôrlē ikˌsperəmənt/