: the 23rd letter of the Greek alphabet see Alphabet Table

psi

2 of 3

noun (2)

: parapsychological psychic phenomena or powers

psi

3 of 3

abbreviation

pounds per square inch

Examples of psi in a Sentence

Recent Examples on the Web
Noun
The trick is to lower your tire pressure to 15 pounds per square inch (psi) or less. Wes Siler, Outside Online, 31 May 2021 So even with a trio of electric motors and a battery pack, plus the beefy V8 and its two gigantic turbochargers capable of pushing up to 36.2 psi of boost, the new Lambo still only weighs 3,725.8 pounds. Michael Teo Van Runkle, Forbes, 17 Aug. 2024 Never mind that black bears have a bite force of 800 psi and a swipe force of 500 pounds. Letters To The Editor, Hartford Courant, 30 July 2024 A day later, the utility announced a boil water advisory for the entire city as pressure fell below the 20 psi threshold that MLGW CEO Doug McGowen said the utility is required to maintain. Lucas Finton, USA TODAY, 23 Jan. 2024 See all Example Sentences for psi 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'psi.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun (1)

Middle English, from Medieval Latin, from Late Greek, from Greek psei

Noun (2)

probably by shortening & alteration from psychic

First Known Use

Noun (1)

15th century, in the meaning defined above

Noun (2)

1942, in the meaning defined above

Time Traveler
The first known use of psi was in the 15th century

Dictionary Entries Near psi

Cite this Entry

“Psi.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/psi. Accessed 11 Sep. 2024.

Kids Definition

psi

noun
ˈsī
: the 23rd letter of the Greek alphabet
Ψ or ψ

Medical Definition

psi

1 of 2 adjective
: relating to, concerned with, or being parapsychological psychic events or powers
psi phenomena

psi

2 of 2 noun
: psi events or phenomena
Last Updated: - Updated example sentences
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