Pressure

(prĕsh'ūr), n. [O. Fr. pressure, It. & Lat. pressura, from Lat. premere. See PRESS, v. t.]

1. The act of pressing, or the condition of being pressed; an urging with force; a squeezing or crushing.
2. (Mech.) The action of a force against some obstacle or opposing force.
3. A constraining force or impulse; that which urges or compels the intellectual or moral faculties to conviction or action; as, the pressure of motives on the mind, or of fear on the conscience.
4. That which afflicts the body, or depresses the spirits; severe affliction, distress, calamity, straits, difficulties, embarrassments, or the distress they occasion; as, the pressure of poverty or want, the pressure of debts, the pressure of taxes, the pressure of afflictions or sorrow.

My own and my people's pressures are grievous. K. Charles. To this consideration he retreats with comfort in all his pressures. Atterbury.

5. Urgency; as, the pressure of business.
6. Impression; stamp; character impressed. “All laws of books, all forms, all pressures pass.” Shak.

Atmospheric pressure, the amount by which the atmosphere presses upon objects immersed in it, equivalent, upon a given area at the earth's surface, to the weight of a column of mercury of the same area and about thirty inches in height, being about 14.7 pounds upon a square inch.