Noun

(anniversaries)

Of a significant event, a day that is an exact number of years (to the day) since the event occurred. Often preceded by an ordinal number indicating the number of years that have elapsed since the event.

Today is the fiftieth anniversary of the end of the war.

(loosely) A day subsequent in time to a given event by some (especially significant) factor other than a year (especially as prefixed by the amount of time in question).

* 1984 , ‘Never Mind the Tranquil Facade’, Time , 27 Feb 1984:

The occasion was the six-month anniversary of the Aug. 8 coup that brought General Óscar Humberto Mejía Victores to power.

* 2002 , ‘Politics this Week’, The Economist , 14 Mar 2002:

In a thinly veiled threat to Saddam Hussein, President George Bush marked the six-month anniversary of September 11th by reiterating America's commitment to prevent rogue countries obtaining weapons of mass destruction.

* 2006 , DB Schrock, Soulmonger Dot Com , p. 28:

Jonathon proposed to his mom on their three-month anniversary of meeting and married her on their fourth.

(more specifically) Such, where the event is a wedding.

We are celebrating our tenth anniversary today.

Noun

(en noun)

A favorable opportunity; a convenient or timely chance.

* Bible, Rom. vii. 11

Sin, taking occasion by the commandment, deceived me.

* Waller

I'll take the occasion which he gives to bring / Him to his death.

The time when something happens.

*, chapter=13

, title= The Mirror and the Lamp , passage=And Vickers launched forth into a tirade very different from his platform utterances. He spoke with extreme contempt of the dense stupidity exhibited on all occasions by the working classes. He said that if you wanted to do anything for them, you must rule them, not pamper them.}}

An occurrence or state of affairs which causes some event or reaction; a motive or reason.

Something which causes something else; a cause.

* 1624 , John Smith, Generall Historie , in Kupperman 1988, p. 130:

it were too vile to say, and scarce to be beleeved, what we endured: but the occasion was our owne, for want of providence, industrie and government [...].

(obsolete) An occurrence or incident.

A particular happening; an instance or time when something occurred.

*{{quote-news, year=2013, date=April 9, author=Andrei Lankov, title=Stay Cool. Call North Korea’s Bluff., work=New York Times citation

, passage=In the last two decades, North Korea has on various occasions conducted highly provocative missile and nuclear tests and promised to turn Seoul into a sea of fire. }}

Need; requirement, necessity.

*

, title=(The Celebrity), chapter=2 , passage=I had occasion […] to make a somewhat long business trip to Chicago, and on my return […] I found Farrar awaiting me in the railway station. He smiled his wonted fraction by way of greeting, […], and finally leading me to his buggy, turned and drove out of town. I was completely mystified at such an unusual proceeding.}}

* Jeremy Taylor

after we have served ourselves and our own occasions

* Burke

when my occasions took me into France

A special event or function.

A reason or excuse; a motive; a persuasion.

* Spenser

Whose manner was, all passengers to stay, / And entertain with her occasions sly.