double-acting

[ duhb-uhl-ak-ting ]

adjective

1. (of a reciprocating engine, pump, etc.) having pistons accomplishing work in both directions, fluid being admitted alternately to opposite ends of the cylinders. Compare single-acting.
2. (of a hinge of a door or the like) permitting movement in either direction from the normal, or closed, position.
3. having twice the usual effectiveness, strength, use, etc.

double-acting

adjective

1. (of a reciprocating engine or pump) having a piston or pistons that are pressurized alternately on opposite sides Compare single-acting
2. (of a hinge, door, etc) having complementary actions in opposed directions

Word History and Origins

Origin of double-acting¹

First recorded in 1835–45

Example Sentences

Schug's paper -- titled, "Acetate acts as a metabolic immunomodulator by bolstering T-cell effector function and potentiating antitumor immunity in breast cancer" -- demonstrates a double-acting mechanism for fighting a particularly aggressive, difficult-to-treat form of breast cancer.

From Science Daily

The Great Depression coincided with the introduction of packaged double-acting baking powder, and that extra boost countered the fruit’s heavy moisture.

From Seattle Times

Lots of double-acting baking powder means there’s no need to add salt, and they’ll be lofty with or without eggs, so they can easily be made vegan.

From Washington Post

Double-acting baking powder, which is the kind that you'll find in the grocery store, produces bubbles in two ways: when it is mixed with wet ingredients and then when it gets heated.

From Salon

Most store-bought baking powder is double-acting and contains a blend of salt acids in which some react quickly, in the presence of liquid, and others more slowly, in the presence of heat, i.e., the oven.

From Washington Post