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\ ˈsī 
, ˈpsī \
, ˈpsī \Definition of psi
(Entry 1 of 3)
: the 23rd letter of the Greek alphabet — see Alphabet Table
psi
noun (2)\ ˈsī \
\Definition of psi (Entry 2 of 3)
: parapsychological psychic phenomena or powers
psi
abbreviationDefinition of psi (Entry 3 of 3)
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More Definitions for psi
psi
adjective\ ˈsī \
\Medical Definition of psi
(Entry 1 of 2)
: relating to, concerned with, or being parapsychological psychic events or powers
psi phenomena
psi
nounMedical Definition of psi (Entry 2 of 2)
: psi events or phenomena
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Time Traveler for psi
The first known use of psi was in the 15th century
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