pounds per square inch pound sovereign • pound sterling · · · Info · Definitions · Synonyms · Characters · · pounds per square inch · · Text Common · · Latin · · Scripts 22 · · Length 5 · · Syllables Definitions · · · (noun) a unit of pressure. Synonyms: pounds per square inch, psi. · · Noun Definition 1 Synonyms · · · psi · · Synonym 1 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 d latin small letter d U+0064 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 q latin small letter q U+0071 r latin small letter r U+0072 s latin small letter s U+0073 u latin small letter u U+0075