PSI

n. 23rd letter of the Greek alphabet

unit of pressure

As a wordPsi (Cyrillic) (Ѱ, ѱ), a letter of the early Cyrillic alphabet, adopted from GreekPsi (Greek) (Ψ, ψ) a letter of the Greek alphabetPsi (comics), a character in DC ComicsPsi (instant messaging client), a popular Jabber client programPsi (parapsychology)
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Noun
1. a unit of pressure
(synonym) pounds per square inch
(hypernym) pressure unit
2. the 23rd letter of the Greek alphabet
(hypernym) letter, letter of the alphabet, alphabetic character
(member-holonym) Greek alphabet

n. psi, 23rd letter of the Greek alphabet

Italian Socialist Party, founded in 1892 in Genoa, its last secretary was Bettino Craxi, the party broke up in 1994 after that most of his members were involved in Tangentopoli