1 a : the weight or force that is produced when something presses or pushes against something else [noncount] ▪ Keep steady pressure on the cap as you turn it. [=press on the cap as you turn it] ▪ Apply pressure to the wound to stop the bleeding. ▪ the pressure of the compressed air inside the chamber ▪ high/low water pressure [=a force that makes a flow of water strong/weak] ▪ Check the car's tire pressure. [=the amount of air inside the tires] ▪ The contents of the bottle are under pressure. [=the contents are tightly pressed into the bottle] [singular] ▪ The animal's jaws can exert a pressure of more than 750 pounds per square inch. — see also blood pressure
b [noncount] : the action of pressing or pushing against something
▪ The horse will respond to the slightest pressure of a rider's knee. ▪ The fruit yields to gentle pressure when it's ripe. 2 [noncount] : the weight of the air in the Earth's atmosphere
▪ the normal air pressure at sea level ▪ atmospheric pressure ▪ Pressure fell [=the air became lighter] as the storm approached. ▪ An area of high/low pressure [=heavy/light air] is moving over the west coast. 3 : the force that you feel when people are trying to persuade or force you to do something by using arguments, threats, etc. [noncount] ▪ He felt pressure from his father to become a doctor. = His father put pressure on him to become a doctor. [=his father was trying to persuade/force him to become a doctor] ▪ The mayor is under pressure to resign. [=people are trying to force the mayor to resign] [count] ▪ He gave in to the social pressures to act and dress like everybody else. ▪ She felt a constant pressure to earn more money. — see also peer pressure 4 : a feeling of stress or anxiety because you have too much to do or because people are depending on you for something [count] ▪ She was dealing with the pressures of everyday life. [noncount] ▪ Can he handle the pressure of the job? ▪ She's been experiencing a lot of pressure at work lately. ▪ They both work well under pressure. [=they work well when the job is stressful] ▪ Her job is high pressure. [=her job is very stressful] — see also high-pressure