\ ˈrō How to pronounce rho (audio) \

Definition of rho

: the 17th letter of the Greek alphabet — see Alphabet Table

Examples of rho in a Sentence

Recent Examples on the Web If the electrons and positrons had originated from persistent rho particles with a characteristic energy or mass, there would have been a bump in the curve. Quanta Magazine, "Physicists Peer Inside a Fireball of Quantum Matter," 30 July 2019 But the rho meson turned out to be something of a special case, and the bootstrap method soon lost momentum. Quanta Magazine, "Physicists Uncover Geometric ‘Theory Space’," 23 Feb. 2017

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

First Known Use of rho

15th century, in the meaning defined above

History and Etymology for rho

Greek rhō, of Semitic origin; akin to Hebrew rēsh resh

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Time Traveler for rho

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The first known use of rho was in the 15th century

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Cite this Entry

“Rho.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/rho. Accessed 24 January 2020.

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Rhyming Dictionary: Words that rhyme with rho

Comments on rho

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a feeling of well-being or elation

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