open

adjective

1》 allowing access, passage, or view; not closed, fastened, or restricted.

2》 exposed to the air or to view or attack; not covered or protected: an open boat.

    ↘(of land) not covered with buildings or trees.

    ↘(open to) vulnerable or subject to.

    ↘(of a town or city) officially declared to be undefended, and so immune under international law from bombardment.

3》 spread out or unfolded.

    ↘(of a book) with the covers parted and able to be read.

4》 admitting customers or visitors; available for business.

    ↘freely available or accessible.

    ↘(of an offer or opportunity) still available.

5》 frank and communicative.

    ↘not concealed; manifest.

    ↘welcoming public discussion, criticism, and enquiry: open government.

6》 (of a matter) not finally settled.

    ↘(often open to) receptive to new ideas.

    ↘(open to) admitting of; making possible.

7》 Music (of a string) allowed to vibrate along its whole length.

    ↘(of a pipe) unstopped at each end.

8》 Phonetics (of a vowel) produced with a relatively wide opening of the mouth and the tongue kept low.

    ↘(of a syllable) ending in a vowel.

9》 (of an electric circuit) having a break in the conducting path.

10》 (of a fabric) loosely knitted or woven.

verb

1》 move (a door, window, etc.) so that it is open.

    ↘undo or remove the cover or fastening of.

    ↘(open on to/into) (of a door, window, etc.) give access to.

2》 unfold or be unfolded; spread out.

    ↘part the covers of (a book) to read it.

    ↘(of a prospect) extend into view.

3》 make or become open for customers or visitors.

    ↘ceremonially declare (a building, road, etc.) to be completed and ready for use.

4》 formally begin or establish.

    ↘(open up or open fire) begin shooting.

    ↘(of a counsel in a law court) make a preliminary statement in (a case) before calling witnesses.

    ↘Bridge make (the first bid) in the auction.

5》 make available or more widely known.

    ↘(open out/up) become more communicative or confiding.

6》 break the conducting path of (an electric circuit).

noun

1》 (the open) outdoors or in the countryside.

    ↘(usu. in phr. in/into the open) a lack of concealment or secrecy.

2》 (Open) a championship or competition with no restrictions on who may compete.

3》 an accidental break in the conducting path for an electric current.

Phrases

the open air a free or unenclosed space outdoors.

in open court in a court of law, before the judge and the public.

open-and-shut (of a case or argument) admitting no doubt or dispute; straightforward.

Derivatives

openable adjective

openness noun

Origin

OE open (adjective), openian (v.), of Gmc origin, from the root of the adverb up.