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1

psi

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noun \ˈsī, ˈpsī\

Definition of psi

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

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Origin and Etymology of psi

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

2

psi

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noun \ˈsī\

Definition of psi

  1. :  parapsychological psychic phenomena or powers

Origin and Etymology of psi

probably by shortening & alteration from psychic

3

psi

abbreviation

Definition of psi

  1. pounds per square inch

See psi defined for English-language learners

Medical Dictionary

1

psi

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adjective \ˈsī\

Medical Definition of psi

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

2

psi

noun

Medical Definition of psi

  1. :  psi events or phenomena

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  1. See words that rhyme with psi

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