psi

or p.s.i.

pounds per square inch.

Words nearby psi

pseudovector, pseudoxanthoma elasticum, psf, psg, pshaw, psi, psi particle, psi phenomenon, psia, psid, psig

Definition for psi (2 of 3)

psi¹

[ sahy, psahy ]

/ saɪ, psaɪ /

noun, plural psis.

the 23rd letter of the Greek alphabet (Ψ, ψ).

the group of consonant sounds represented by this letter.

Origin of psi

1350–1400; Middle English < Greek pseî

Definition for psi (3 of 3)

psi²

[ sahy ]

/ saɪ /

noun

any purportedly psychic phenomenon, as psychokinesis, telepathy, clairvoyance, or the like.

Compare pseudoscience, parapsychology.

Origin of psi

1940–45; shortening of psychic or parapsychic

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for psi

Will PSI (private sector involvement) become common in future bailouts?
What Bailout? Six Reasons to Love Cyprus|Kevin Fallon|March 18, 2013|DAILY BEAST
In 2009, Judd lent her voice to a PSI World Malaria Day PSA.
Ashley Judd’s Fiery Speeches on Favorite Political Causes (VIDEO)|Caitlin Dickson|December 6, 2012|DAILY BEAST
The fraternities involved in the alleged drug sales were Alpha Epsilon Pi, Pi Kappa Alpha and Psi Upsilon.
Columbia University Drug Bust|Joshua Robinson, Lloyd Grove|December 8, 2010|DAILY BEAST
PSI board member Ashley Judd is a celebrated actress, activist, and humanitarian.
Can Safe Sex Save the World?|Ashley Judd|July 3, 2010|DAILY BEAST

Take Action: Ashley Judd works with the nonprofit PSI, investing in the power of women to lift communities out of poverty.
Can Safe Sex Save the World?|Ashley Judd|July 3, 2010|DAILY BEAST
"There isn't any rule about who can have psi talent," I argued.
Sense from Thought Divide|Mark Irvin Clifton
I know you aren't a Psi, and thus aren't subject to our discipline, but I think it's time we exchanged some information.
The Right Time|Walter Bupp
And in this area was a wash of psi radiation such as he had never experienced before.
Deathworld|Harry Harrison
With them swinging at his side, he stole out of the Psi Delta house, crossed the campus, stopped.
Gladiator|Philip Wylie
I assume that you have found the experimental conditions which let psi powers operate without hindrance.
The Leader|William Fitzgerald Jenkins (AKA Murray Leinster)

British Dictionary definitions for psi (1 of 2)

psi¹

abbreviation for

pounds per square inch

British Dictionary definitions for psi (2 of 2)

psi²

/ (psaɪ) /

noun

the 23rd letter of the Greek alphabet (Ψ, ψ), a composite consonant, transliterated as ps

paranormal or psychic phenomena collectively
(as modifier)psi powers

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for psi

psi

[ sī, psī ]

n.

The 23rd letter of the Greek alphabet.