مکش

Also known as sucking

thumb|240x240px|Gasses or liquids that move along a pressure gradient can exert forces on objects. Suction is the day-to-day term for the movement of gases or liquids along a pressure gradient with the implication that the movement occurs because the lower pressure pulls the gas or liquid. However, the forces acting in this case do not originate from just the lower pressure side, but instead from the side of the higher pressure, as a reaction to the pressure difference.