dark matter

noun
Updated on: 8 Nov 2017

Definition of dark matter

: nonluminous matter not yet directly detected by astronomers that is hypothesized to exist to account for various observed gravitational effects

Recent Examples of dark matter from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dark matter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of dark matter

1979


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