necessity

ne‧ces‧si‧ty /nəˈsesəti, nɪˈsesəti/ BrE AmE noun (plural necessities)
[Word Family: noun: ↑necessity, the necessaries, the necessary; verb: ↑necessitate; adverb: ↑necessarily ≠ ↑unnecessarily; adjective: ↑necessary ≠ ↑unnecessary]
[Date: 1300-1400; Language: French; Origin: necessité, from Latin necessitas, from necesse; ⇨ ↑necessary]
1. [countable] something that you need to have in order to live OPP luxury:
She saw books as a necessity, not a luxury.
A car is an absolute necessity if you live in the country.
the basic/bare necessities
A lot of families cannot even afford to buy the basic necessities of life.
2. [uncountable] when something is necessary
necessity for
He emphasized the necessity for good planning and management.
the necessity of (doing) something
This illustrates the necessity of keeping accurate records of your work.
Many teachers are now questioning the necessity of formal exams.
through/out of necessity
He only remained with the group out of necessity.
economic/practical/political etc necessity
I’m afraid it’s become a matter of economic necessity.
3. [countable] something that must happen, even if it is unpleasant:
Taxes are a regrettable necessity.
4. of necessity formal used when something happens in a particular way because that is the only possible way it can happen:
Many of the jobs are, of necessity, temporary.
5. necessity is the mother of invention used to say that if someone really needs to do something, they will find a way of doing it

Oxford Advanced Learner's Dictionary

necessity

ne·ces·sity [necessity necessities] [nəˈsesəti] [nəˈsesəti] noun
1. uncountable the fact that sth must happen or be done; the need for sth
• ~ (for sth) We recognize the necessity for a written agreement.
• ~ (of sth/of doing sth) We were discussing the necessity of employing more staff.
• ~ (for sb) to do sth There had never been any necessity for her to go out to work.
• There is absolutely no necessity for you to be involved.

• This is, of necessity, a brief and incomplete account.

2. countable a thing that you must have and cannot manage without
• Many people cannot even afford basic necessities such as food and clothing.

• Air-conditioning is an absolute necessity in this climate.

3. countable, usually singular a situation that must happen and that cannot be avoided
• Living in London, he felt, was an unfortunate necessity.
more at make a virtue of necessity at virtue
Idiom: necessity is the mother of invention
Word Origin:
late Middle English: from Old French necessite, from Latin necessitas, from necesse ‘be needful’.
Example Bank:
• Culling of the animals was born out of the necessity for successful conservation.
• Driven by financial necessity, she decided to give up her writing career.
• Food is a necessity of life.
• He argued that nuclear weapons were a political necessity.
• He is changing job out of necessity, not because he particularly wants to.
• I've never felt the necessity to rely on such a strict rule.
• Most disputes can be resolved without the necessity of going to court.
• Most of the women are forced, through economic necessity, to work in part-time low-paid jobs.
• Mrs R has been spared the necessity of having to give evidence.
• Necessity forced an urgent solution.
• Observers stressed the necessity for the ceasefire to be observed.
• Policies which address these issues are an urgent necessity.
• She saw the necessity to make an immediate impression on him.
• Sleep is an absolute necessity for life.
• The company sees no necessity for a more cautious approach to investment.
• The people in the rural areas use mud bricks only as an immediate, practical necessity.
• The visit will, of necessity, be brief.
• There's no necessity for you to come.
• These animals don't like water but will swim if the necessity arises.
• They have accepted the necessity of greater state intervention.
• They have nothing but the barest necessities.
• This rule is carried no farther than necessity requires.
• Where necessity demands, we can seat more guests in the gallery.
• You can dial direct without the necessity of going through the operator.
• the necessity to earn a living

• Living in London he felt, was an unfortunate necessity.

Cambridge Advanced Learner's Dictionary

necessity / nəˈses.ɪ.ti / / -ə.t̬i / noun

C1 [ U ] the need for something:

You can come early if you want to, but there's no necessity for it.

[ + to infinitive ] Is there any necessity to reply to her letter?

The report stresses the necessity of eat ing plenty of fresh fruit and vegetables.

With a personal fortune of six million pounds, she certainly doesn't work out of necessity (= because she needs to) .

We'll employ extra staff to help out as and when the necessity arises (= when we need to) .

C1 [ C ] something that you need, especially in order to live:

We brought only the bare necessities with us.

He regarded music as one of life's necessities.

Collins Advanced Learner’s English Dictionary

necessity

[nɪse̱sɪti]
necessities
1) N-UNCOUNT: usu with supp The necessity of something is the fact that it must happen or exist.
  There is agreement on the necessity of reforms...
  As soon as the necessity for action is over the troops must be withdrawn...
  Most women, like men, work from economic necessity...
  Some people have to lead stressful lifestyles out of necessity.
  ●
  PHRASE: usu PHR before v, PHR n/adj/adv If you say that something is of necessity the case, you mean that it is the case because nothing else is possible or practical in the circumstances. [FORMAL]
  The assembly line of necessity kept moving...
  Negotiations between the enemies are of necessity indirect.
  Syn:
  inevitably
2) N-COUNT A necessity is something that you must have in order to live properly or do something.
  Water is a basic necessity of life.
  ...food, fuel and other daily necessities.
  Syn:
  essential
  Ant:
  luxury
3) N-COUNT: usu sing A situation or action that is a necessity is necessary and cannot be avoided.
  The President pleaded that strong rule from the centre was a regrettable, but temporary necessity.

Merriam-Webster's Advanced Learner's Dictionary

necessity

ne·ces·si·ty /nɪˈsɛsəti/ noun, pl -ties
1 [count] : something that you must have or do : something that is necessary
• Sunscreen is an absolute necessity for the beach.
• food, clothes, and other basic necessities
• Getting plenty of rest is a necessity.
• Without a car, living close to work is a necessity.
• All we took with us on our hiking trip were the bare necessities.
• Many families cannot even afford the basic/bare necessities of life. [=things that a person must have in order to survive]
2 [noncount] formal : the quality of being necessary - usually + of or for
• She talked about the necessity of having the right training. [=she said that having the right training is necessary]
• He questioned the necessity for the change. [=he questioned whether the change was necessary]
by necessity or out of necessity : because of conditions that cannot be changed
• The process is by necessity a slow one. [=the process is necessarily slow; the slowness of the process cannot be avoided]
• He works two jobs out of necessity. [=because it is necessary]
make a virtue (out) of necessity
- see virtue
necessity is the mother of invention
- see ¹mother
of necessity formal
- used to say that something must happen or must be the way it is
• Further changes to the company will occur of necessity.