Noun

(uncountable) The quality of being different.

(countable) A characteristic of something that makes it different from something else.

* {{quote-magazine, title=Towards the end of poverty

, date=2013-06-01, volume=407, issue=8838, page=11, magazine=(The Economist) citation , passage=But poverty’s scourge is fiercest below $1.25 (the average of the 15 poorest countries’ own poverty lines, measured in 2005 dollars and adjusted for differences in purchasing power): people below that level live lives that are poor, nasty, brutish and short.}}

(countable) A disagreement or argument.

We have our little differences , but we are firm friends.

* Shakespeare

What was the difference ? It was a contention in public.

* T. Ellwood

Away therefore went I with the constable, leaving the old warden and the young constable to compose their difference as they could.

(countable, uncountable) Significant change in or effect on a situation or state.

* 1908 , (Kenneth Grahame), (The Wind in the Willows)

The line of the horizon was clear and hard against the sky, and in one particular quarter it showed black against a silvery climbing phosphorescence that grew and grew. At last, over the rim of the waiting earth the moon lifted with slow majesty till it swung clear of the horizon and rode off, free of moorings; and once more they began to see surfaces—meadows wide-spread, and quiet gardens, and the river itself from bank to bank, all softly disclosed, all washed clean of mystery and terror, all radiant again as by day, but with a difference that was tremendous.

(countable) The result of a subtraction; sometimes the absolute value of this result.

(obsolete) Choice; preference.

* Spenser

That now be chooseth with vile difference / To be a beast, and lack intelligence.

(heraldry) An addition to a coat of arms to distinguish two people's bearings which would otherwise be the same. See augmentation and cadency.

(logic) The quality or attribute which is added to those of the genus to constitute a species; a differentia.

(logic circuits) A Boolean operation which is TRUE when the two input variables are different but is otherwise FALSE; the XOR operation ($\backslash scriptstyle\; A\; \backslash overline\; B\; +\; \backslash overline\; A\; B$).

(relational algebra) the set of elements that are in one set but not another ($\backslash scriptstyle\; A\; \backslash overline\; B$).

Noun

(en noun)

An act or instance of making or becoming open.

The daily openings of the day lily bloom gives it its name.

He remembered fondly the Christmas morning opening of presents.

Something that is open.

A salamander darted out of an opening in the rocks.

He slipped through an opening in the crowd.

An act or instance of beginning.

There have been few factory and store openings in the US lately.

Their opening of the concert with ''Brass in Pocket'' always fires up the crowd.

Something that is a beginning.

# The first performance of a show or play by a particular troupe.

They were disappointed at the turnout for their opening , but hoped that word would spread.

# The initial period a show at an art gallery or museum is first opened, especially the first evening.

# The first few measures of a musical composition.

# (chess) The first few moves in a game of chess.

John spends two hours a day studying openings , and another two hours studying endgames.

A vacant position, especially in an array.

Are there likely to be any openings on the Supreme Court in the next four years?

# A time available in a schedule.

If you'd like to make a booking with us, we have an opening at twelve o'clock.

The only two-hour openings for the hockey rink are between 1AM and 5AM.

# An unoccupied employment position.

We have an opening in our marketing department.

An opportunity, as in a competitive activity.

* {{quote-news

, year=2010 , date=December 29 , author=Sam Sheringham , title=Liverpool 0 - 1 Wolverhampton , work=BBC citation , page= , passage=The Reds carved the first opening of the second period as Glen Johnson's pull-back found David Ngog but the Frenchman hooked wide from six yards. }}