Help Wordnik hunt for a million missing words by backing our Kickstarter!


from The American Heritage® Dictionary of the English Language, 4th Edition

  • adj. Able to act or work automatically.

from the GNU version of the Collaborative International Dictionary of English

  • adj. Acting of or by one's self or by itself; -- said especially of a machine or mechanism which is made to perform of or for itself what is usually done by human agency; automatic.

from The Century Dictionary and Cyclopedia

  • Acting of or by itself: noting any automatic contrivance for superseding the manipulation which would otherwise be required in the management of a machine: as, the self-acting feed of a boring-mill, whereby the cutters are carried forward by the general motion of the machine.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adj. designed to activate or move or regulate itself


Sorry, no etymologies found.


  • My dear Darwin, – I have been so repeatedly struck by the utter inability of numbers of intelligent persons to see clearly, or at all, the self-acting and necessary effects of Natural Selection, that I am led to conclude that the term itself, and your mode of illustrating it, however clear and beautiful to many of us, are yet not the best adapted to impress it on the general naturalist public.


  • For, he wrote, "I am repeatedly struck by the utter inability of numbers of intelligent persons to see clearly, or at all, the self-acting and necessary effects of Natural Selection."

    The Debate Over Intelligent Design

  • A self-acting knocker gives a treble knock -- door is opened by a

    A Dialogue for the Year 2130

  • A self-acting apparatus supplied the three travelers with air to breathe.

    Round the Moon

  • Are we not ourselves creating our successors in the supremacy of the earth? daily adding to the beauty and delicacy of their organisation, daily giving them greater skill and supplying more and more of that self-regulating self-acting power which will be better than any intellect?


  • Revolution began in the wake of the introduction of the self-acting mule (spinning machine) and of widespread unrest because of economic hardship culminating in a general strike (1854) among textile workers.

    e. The Iberian Peninsula

  • Safeguarding the switchgear against unintentional or self-acting reclosing is an important safety measure.

    4. Low-voltage switchgear and distribution systems

  • Till 1988, one prototype was realized to demonstrate the physics of the self-acting siphonic heat transfer system.

    Chapter 8

  • By comparison, the two automatic ( "self-acting") whipping machines patented in 1886 and 1895 for use in sweep powers appear ludricrous and harmless.

    5. Draft Animals: All Work and No Play?

  • Newcomen's achievement lay in devising it in thoroughly practicable form — steam in a cylinder, fitted with a piston, is condensed, leaving a void, so that the external atmospheric pres - sure can act on the piston — and in making the engine automatic or self-acting.



Log in or sign up to get involved in the conversation. It's quick and easy.