psi

Look up psi or PSI in Wiktionary, the free dictionary.

Psi may refer to:

As a word

• 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/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 functions, the Chebyshev function, or the Dedekind psi function.
• ψ is often used to denote the stream function in two-dimensional flows.

As an abbreviation

PSI

In Computing:

• Program Specific Information, part of the MPEG transport stream protocol. Metadata for digital transmission
• PSI (computational chemistry) software
• Personal Software Inspector, a host-based software vulnerability scanner from Secunia

PSI can be an abbreviation for:

• Pandemic Severity Index by the US Centers for Disease Control and Prevention
• Partai Sosialis Indonesia ("Indonesian Socialist Party")
• Paranormal Site Investigators, an education and research charity in the UK
• Italian Socialist Party (Partito Socialista Italiano)
• Para-social identification
• 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
• Persian State of Iran
• Pitch Shifter Industries, an acronym used by the British band Pitchshifter
• Photosystem I, a protein complex involved in photosynthesis
• 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
• Portuguese Stock Index (PSI-20), a benchmark stock market index of companies that trade on Euronext Lisbon, the main stock exchange of Portugal
• Pounds per square inch
• Presentence Investigation
• Process Safety Incident
• Professional Secretaries International
• Professional Skills Institute
• Professors for a Strong Israel
• Proliferation Security Initiative, an international effort originally put forward by the United States to interdict transfer of banned weapons and weapons technology.
• 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 (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 fiction

• In Babylon 5 universe, Psi Corps is the ruling body of Earth's telepaths
• PSI is the ability used by characters from the EarthBound series
• Psi-Ops, a video game by Midway where characters use psychic powers.

This disambiguation page lists articles associated with the same title. If an internal link led you here, you may wish to change the link to point directly to the intended article.

Other

PSI Power (Earthbound/MOTHER series)