Is it ensure, insure, or assure?
late 14c., "suffering, anguish; act or fact of pressing on the mind or heart," from Old French presseure "oppression; torture; anguish; press" (for wine or cheeses), "instrument of torture" (12c.) and directly from Latin pressura "action of pressing," from pressus, past participle of premere "to press" (see press (v.1)).
Literal meaning "act or fact of pressing" in a physical sense is attested from early 15c. Meaning "moral or mental coercing force" is from 1620s; meaning "urgency" is from 1812. Scientific sense in physics is from 1650s. Pressure cooker is attested from 1915; figurative sense is from 1958. Pressure point is attested from 1876. Pressure-treated, of woods, is from 1911.
"to pressurize," 1886, American English, from pressure (n.). Meaning "to exert pressure on" (someone) is attested by 1922. Related: Pressured; pressuring.
pressure pres·sure (prěsh'ər)
The act of pressing or condition of being pressed.
A stress or force acting in any direction against resistance.
Force applied uniformly over a surface, measured as force per unit of area.
The force per unit area that one region of a gas, liquid, or solid exerts on another. Pressure is usually measured in Pascal units, atmospheres, or pounds per square inch. ◇ A substance is said to have negative pressure if some other substance exerts more force per unit area on it than vice versa. Its value is simply the negative of the pressure exerted by the other substance.