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

Word History

Etymology

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

First Known Use

15th century, in the meaning defined above

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

Browse Nearby Words

Cite this Entry

“Rho.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rho. Accessed 27 Jul. 2026.

Kids Definition

: the 17th letter of the Greek alphabet
Ρ or ρ
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