Definition of "psi" [psi]

• The 23rd letter of the Greek alphabet. See Table at alphabet. (noun)
• Parapsychological phenomena or abilities considered as a group. (noun)
• Pounds per square inch (abbreviation)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In spinor form the wave-field is psi = (psi_A, psi_ {A’})."
• "The term psi was coined as a neutral term for psychic phenomena in 1942 by British psychologist Robert Thouless."
• "Virtually all meditative traditions take for granted that what we call psi is simply the initial stages of awareness of deeper levels of reality."