of unknown origin

phrase

—used to say that the source or cause of something is not known
a disease of unknown origin

Browse Nearby Words

of two minds
of unknown origin
of unsound mind
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Cite this Entry

“Of unknown origin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/of%20unknown%20origin. Accessed 10 Mar. 2026.

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