suction pump

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A pump for drawing up a liquid by means of suction produced by a piston drawn through a cylinder.

Century Dictionary and Cyclopedia

1. n. A pump having a barrel placed above the level of the water to be drawn, a suction-pipe extending from the barrel down into the water to be raised, an inlet-valve opening inward or toward the piston, and an outlet-valve in the piston. When the piston is raised, the air in the barrel below the piston expands, its tension is correspondingly diminished, and the pressure of the external air upon the surface of the liquid outside forces it up into the suction-tube. See pump.
2. n. As a piece of chemical apparatus, same as filter-pump.

GNU Webster's 1913

1. n. the common pump, in which the water is raised into the barrel by atmospheric pressure. See Illust. of Pump.

WordNet 3.0

1. n. a pump for raising fluids by suction