Breadcrumb Home > Thesaurus > P Synonyms of psi Find synonyms for: Noun 1. pounds per square inch, psi, pressure unit usage: a unit of pressure 2. psi, letter, letter of the alphabet, alphabetic character usage: the 23rd letter of the Greek alphabet WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of psi (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: recherch Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language