psi has definitions from the field of physics
1
[ noun ] (physics) a unit of pressure

Used in print

(1961 Research Highlights of the National Bureau of...)

Over a temperature range from 25 to 200 * * f and at pressures up_to 250 atm , an overload of 300 psi , applied for a period of one day , results in an uncertainty in the pressure of , at_most , one millimeter_of_mercury .

Related terms

pressure_unit

2
[ noun ] the 23rd letter of the Greek alphabet

Related terms

letter Greek_alphabet

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