Psi 24779 225403095 2008-07-13T14:25:55Z RDBury 433687 /* In mathematics */ Change link to tangential angle {{TOCright}} {{wiktionarypar|psi|PSI}} '''Psi''' may refer to: ==As a word== * [[Psi (letter)|Psi (Greek)]] (Ψ, ψ) a letter of the Greek alphabet * [[Psi (Cyrillic)]] (Ѱ, ѱ), a letter of the early Cyrillic alphabet, adopted from Greek * [[Psi (instant messaging client)]], a popular Jabber client program * [[Psi (parapsychology)]] * [[Psi-Theory]], a theory about the human mind, a cognitive architecture * [[Psi hit]], a parapsychological experimentation term * ''[[Psi Factor: Chronicles of the Paranormal]]'', a Canadian television series ==As a Greek letter== * [[J particle|J/ψ particle]], a subatomic particle * [[Wavefunction]] in Quantum Mechanics, ψ * In physical chemistry, Ψ represents [[water potential]], the potential energy of a water solution relative to pure water * Ψ stands for [[psychology]] and psychologist, often used in the logo of various psychological associations * ΨΧ ([[Psi Chi]]), National Honor Society in Psychology ==In mathematics== * ψ is used to denote [[tangential angle]] of a curve. * ψ can also denote the [[digamma function]], the [[polygamma function]]s, or the [[Dedekind psi function]] ==As an abbreviation== ===PSI=== PSI can be an abbreviation for: * [[Italian Socialist Party]] (''Partito Socialista Italiano'') * [[Pandemic Severity Index]] by the US Centers for Disease Control and Prevention * [[Paul Scherrer Institute]] in Villigen, Switzerland * [[Pechersk School International]] in Kyiv, Ukraine * [[Permanent Staff Instructor]] in the British Army * [[Permanent Subcommittee on Investigations]] (PSI) of the US Senate * [[Pneumonia severity index]] * [[Pollutant Standards Index]], an air pollution index developed by the US Environmental Protection Agency * [[Population Services International]], an international healthcare NGO based in Washington DC * [[PSI-20|Portuguese Stock Index]] (PSI-20), a benchmark stock market index of companies that trade on Euronext Lisbon, the main stock exchange of Portugal * [[Presentence Investigation]] * [[Professional Secretaries International]] * [[Professors for a Strong Israel]] * [[Program Specific Information]], part of the MPEG transport stream protocol. Metadata for digital transmission * [[Proliferation Security Initiative]] * [[Protein Structure Initiative]], a structural genomics initiative of the U.S. NIGMS * [[Public Services International]], a global union federation of public sector trade unions * [[PSI (computational chemistry)]] software * [[PSI (prion)]], an infectious protein in yeast * [[PSI Records]], a record label * [[Statisticians In The Pharmaceutical Industry]], the PSI acronym (rather than SPI) is chosen for its relation to the Greek letter Ψ, commonly used in statistical formulae ===psi=== * [[Pounds per square inch]], a unit of pressure ===pSi=== * [[Porous silicon]] ==In comics== * [[Psi (comics)]], a character in DC Comics * ''[[Psi-Force]]'', a comic series * [[Psi-Hawk]], a comic character * ''[[Psi Lords]]'', a comic series * [[Psi Division]], a division in the Judge Dredd and 2000 AD series of comics ==In music== * [[Psi Power]], a 1978 song by the UK rock group Hawkwind * [[Psi Com]], a 1980s rock band ==In video games== * In the [[EarthBound]] series, the main characters use psychic abilities known as PSI pronounced PK. Examples of these powers are PSI(PK) Fire and PSI(PK)Freeze. ==In fiction == * In [[Babylon 5]] universe, [[Psi Corps]] is the ruling body of Earth's telepaths {{disambig}} [[cs:Psi]] [[da:Psi]] [[de:Psi (Begriffsklärung)]] [[es:Psi]] [[eo:PSI]] [[fr:Psi]] [[ko:PSI]] [[it:PSI]] [[nl:Psi]] [[ja:PSI]] [[pl:Psi]] [[pt:Psi]] [[ru:Psi (значения)]] [[fi:PSI]] [[sv:Psi (olika betydelser)]]