Revision as of 10:20, 28 June 2005 by Mutante
- The twenty-third letter of the [Classical Greek] and [Modern Greek], the twenty-forth letter of [Old Greek] and [Ancient Greek] Alphabet.
- In mathematics (Ѱ, ѱ) is the angle between the tangent and the x-axis in the intrinsic coordinates system.
- The lower-case letter ψ is used as the symbol for the wave function in quantum mechanics.
- In high-energy physics, Ψ refers to a meson also called the J/Ψ particle
- Psi is also a popular Jabber client.
- Psi was also a character on the popular game and television series, Pokémon.
- The Italian Socialist Party (Partito Socialista Italiano)
- Pounds per square inch (PSI).