helioseismology

noun

he·​lio·​seis·​mol·​o·​gy ˌhē-lē-ō-sīz-ˈmä-lə-jē 

-sīs-

: the study of vibrations in the material that makes up the Sun

Scientists have discovered that the sun is vibrating, and they can detect this "global oscillation" using the new techniques of "helioseismology," which are similar to those used in terrestrial seismology.

—Madeleine Jacobs, Chicago Tribune, 29 Dec. 1985

Word History

First Known Use

1979, in the meaning defined above

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