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1

psi

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noun \ˈsī, ˈpsī\

Definition of psi

  1. :  the 23d letter of the Greek alphabet — see alphabet table



Origin of psi

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


First Known Use: 15th century

Rhymes with psi


2

psi

play
noun \ˈsī\

Definition of psi

  1. :  parapsychological psychic phenomena or powers



Origin of psi

probably by shortening & alteration from psychic


First Known Use: 1942


3

psi

abbreviation

Definition of psi

  1. pounds per square inch




Learn More about psi

  1. Medical Dictionary: Definition of "psi"


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