interferometer

in·ter·fer·om·e·ter

noun
\ˌint-ə(r)-fə-ˈräm-ət-ər, -ˌfir-ˈäm-\

Definition of INTERFEROMETER

: an instrument that utilizes the interference of waves (as of light) for precise determination especially of wavelength, spectral fine structure, indices of refraction, and very small linear displacements

—in·ter·fer·o·met·ric \-ˌfir-ə-ˈme-trik\ adjective

—in·ter·fer·o·met·ri·cal·ly \-tri-k(ə-)lē\ adverb

—in·ter·fer·om·e·try \-fə-ˈräm-ə-trē, -ˌfir-ˈäm-\ noun, plural in·ter·fer·om·e·tries