psi
Psi (noun) means the 23rd letter of the Greek alphabet (Ψ, ψ). Example: “Psi comes near the end of the Greek alphabet, just before omega.”
How to use psi
Learner’s notesIn plain EnglishEither the Greek letter, or (informally) mental/psychic energy, or the pressure unit "pounds per square inch."
Context decides the meaning — psi in a maths equation is the letter, psi in a tyre gauge is pressure, and psi in a sci-fi story is psychic power.
Word forms
psis plural
Fill the gap
Can you complete this real example?
_____ comes near the end of the Greek alphabet, just before omega.
Etymology
From the Greek letter name psi (Ψ), going back to Ancient Greek psei.
Synonyms
View more →Frequently asked questions
What does “psi” mean?
The word “psi” means the 23rd letter of the Greek alphabet (Ψ, ψ). In plain terms, either the Greek letter, or (informally) mental/psychic energy, or the pressure unit "pounds per square inch.".
How do you pronounce “psi”?
“Psi” is pronounced pseye (/psaɪ/ in IPA).
How do you use “psi” in a sentence?
Here is “psi” used in a sentence: “Psi comes near the end of the Greek alphabet, just before omega.”
What part of speech is “psi”?
Depending on how it is used, “psi” can be a noun and a symbol.
Where does the word “psi” come from?
The word “psi” comes from Ancient Greek. From the Greek letter name psi (Ψ), going back to Ancient Greek psei.
Is “psi” a common word?
“Psi” is an uncommon word in modern English.
How many meanings does “psi” have?
“Psi” has 3 distinct senses listed in this dictionary. The most common is: the 23rd letter of the Greek alphabet (Ψ, ψ).
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