English Reference

Word

opening

Phoneticsopen·ing

US/ˈoʊpənɪŋ/

UK/ˈəʊpənɪŋ/

Definitions

01a gap or hole

B1

n. a hole or space that something can pass through.

n. an aperture or gap that permits passage or visibility.

“The cat squeezed through a small opening in the garden fence.”

“The climbers discovered a narrow opening in the rock face that led to a hidden cavern system.”

Synonyms

Antonyms

02the start of an event

B1

n. the beginning of a show, ceremony, or story.

n. the initial part or commencement of a performance, event, or literary work.

“The opening of the new art gallery attracted hundreds of visitors.”

“The novel's dramatic opening immediately establishes a sense of tension that persists throughout the first three chapters.”

Antonyms

03a job vacancy

B2

n. a job that is available for someone to start.

n. a vacant position or opportunity for employment within an organisation.

“The company has an opening for a junior designer in the marketing team.”

“Although the firm is currently downsizing, they have kept one opening available for a specialist in international law.”

04mathematical morphology

C2 · Math

n. a specific way of changing a shape in computer math.

n. the dilation of the erosion of a set, used to remove small objects or noise from an image.

“The engineer used an opening to clean up the digital image.”

“Applying an opening to the binary image effectively eliminated the salt-and-pepper noise without significantly altering the larger structural components.”

Technical

Antonyms

05the first in a series

B1

adj. happening at the very beginning of something.

adj. pertaining to the start or first stage of a series of events or a period of time.

“The opening scene of the movie was filmed in London.”

“The opening remarks of the conference set a collaborative tone for the subsequent panel discussions.”

Synonyms

Antonyms

Real-World Examples

“For example, in the opening scene, Theseus’s “earthlier happy is the rose distill’d” becomes “happier is the rose plucked for perfume”.”
The Guardian · 14 Aug 2026
“And there is a man sitting at a desk, welcoming us to the theatre and opening a folder.”
The Guardian · 13 Aug 2026
“But the new owners say they see "real opportunities" for growth, including opening new standalone shops.”
BBC News · 6 Aug 2026
“The first thing most people will want to know is if opening a window and using a fan at the same time will cool down their home.”
BBC News · 8 Jul 2026

Etymology

From Middle English openynge, openande, openand, from Old English openiende, from Proto-West Germanic opanōndī, from Proto-Germanic upanōndz, present participle of *upanōną (“to open”), equivalent to open + -ing. Cognate with West Frisian iepenjend, Dutch openend, German öffnend, Swedish öppnande, Icelandic opnandi.

From Middle English openyng, openynge, openunge, from Old English openung (“an opening”), from Proto-West Germanic opanungu, from Proto-Germanic upanungō (“an opening”), equivalent to open + -ing. Cognate with Saterland Frisian Eepenge, Epenge (“an opening”), West Frisian iepening (“an opening”), Dutch opening (“an opening”), German Öffnung (“an opening”), Danish åbning (“an opening”), Swedish öppning (“an opening”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Collocations

opening the dooropening newopening dayopening nightopening offeropening weekendopening argumentsopening ceremony

Word family

Idioms

opening of an envelope — Any kind of event or activity that may contribute to one's self-promotion or visibility in society.

Domain

Mathematics

This entry

Level
B2 · Upper Intermediate
Frequency
Very common
Updated

Scan code

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English Reference