\ ˈsī How to pronounce psi (audio) , ˈpsī How to pronounce psi (audio) \

Definition of psi

 (Entry 1 of 3)

: the 23rd letter of the Greek alphabet — see Alphabet Table
\ ˈsī How to pronounce psi (audio) \

Definition of psi (Entry 2 of 3)

: parapsychological psychic phenomena or powers

Definition of psi (Entry 3 of 3)

pounds per square inch

First Known Use of psi

Noun (1)

15th century, in the meaning defined above

Noun (2)

1942, in the meaning defined above

History and Etymology for psi

Noun (1)

Middle English, from Medieval Latin, from Late Greek, from Greek psei

Noun (2)

probably by shortening & alteration from psychic

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Time Traveler for psi

Time Traveler

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

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Cite this Entry

“Psi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psi. Accessed 29 Feb. 2020.

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More Definitions for psi

\ ˈsī How to pronounce psi (audio) \

Medical Definition of psi

 (Entry 1 of 2)

: relating to, concerned with, or being parapsychological psychic events or powers psi phenomena



Medical Definition of psi (Entry 2 of 2)

: psi events or phenomena

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Rhyming Dictionary: Words that rhyme with psi

Spanish Central: Translation of psi

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