phi

noun
\ ˈfī How to pronounce phi (audio) \

Definition of phi

: the 21st letter of the Greek alphabet — see Alphabet Table

First Known Use of phi

15th century, in the meaning defined above

History and Etymology for phi

Middle Greek, from Greek phei

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Time Traveler for phi

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

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Dictionary Entries Near phi

phew

phi

phial

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Cite this Entry

“Phi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phi. Accessed 5 Jul. 2022.

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More from Merriam-Webster on phi

Britannica.com: Encyclopedia article about phi

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