Noun

The state of being certain.

* Fisher Ames

The certainty of punishment is the truest security against crimes.

An instance of being certain.

A fact or truth unquestionably established.

* November 2 2014 , Daniel Taylor, " Sergio Agüero strike wins derby for Manchester City against 10-man United," guardian.co.uk

Yet the truth is that City would probably have been coasting by that point if the referee, Michael Oliver, had not turned down three separate penalties, at least two of which could be accurately described as certainties .

* 1824 , (Walter Savage Landor), Imaginary Conversations Volume 1

Certainties are uninteresting and sating.

Noun

(necessities)

The quality or state of being necessary, unavoidable, or absolutely requisite.

* {{quote-magazine, date=2013-06-28, author=(Joris Luyendijk)

, volume=189, issue=3, page=21, magazine=(The Guardian Weekly) , title= Our banks are out of control , passage=Seeing the British establishment struggle with the financial sector is like watching an alcoholic […].  Until 2008 there was denial over what finance had become. […]  But the scandals kept coming, […]. A broad section of the political class now recognises the need for change but remains unable to see the necessity of a fundamental overhaul.}}

The condition of being needy or necessitous; pressing need; indigence; want.

That which is necessary; a requisite; something indispensable.

*

Love and compassion are necessities , not luxuries. Without them humanity cannot survive.

That which makes an act or an event unavoidable; irresistible force; overruling power; compulsion, physical or moral; fate; fatality.

* 1804 , Wordsworth,

I stopped, and said with inly muttered voice,

'It doth not love the shower, nor seek the cold:

This neither is its courage nor its choice,

But its necessity in being old.

The negation of freedom in voluntary action; the subjection of all phenomena, whether material or spiritual, to inevitable causation; necessitarianism.

(legal) Greater utilitarian good; used in justification of a criminal act .

(legal, in the plural) Indispensable requirements (of life).