self-acting

American  

[self-ak-ting] / ˈsɛlfˈæk tɪŋ /

adjective

1. acting by itself; automatic.

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self-acting British  

adjective

1. not requiring an external influence or control to function; automatic

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Other Word Forms

• self-action noun

Etymology

Origin of self-acting

First recorded in 1670–80

Example Sentences

Its new rule said bump stocks were illegal machine guns because they function as “a self-acting or self-regulating mechanism that allows the firing of multiple rounds through a single function of the trigger.”

From Los Angeles Times • Feb. 28, 2024

It said the bump stock device functions as “a self-acting or self-regulating mechanism that allows the firing of multiple rounds through a single pull of the trigger.”

From Los Angeles Times • Nov. 3, 2023

She apparently experienced entrancement to absolute unconsciousness, so that she became, for the time being, literally a tool—no more self-acting, and therefore no more responsible, than a pen, a pencil, or a speaking-trumpet.

From Witchcraft of New England Explained by Modern Spiritualism by Putnam, Allen

The machine was on its finishing round; three seconds more, and the self-acting steam-valve has shut, the engine slows up to a stop, and its builder, with a quickened pulse, bends eagerly forward.

From Hope Benham A Story for Girls by Perry, Nora

The engine is self-acting, and can be driven either by hand or by a steam-engine or other motive power.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" by Various