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Related to necessary: Necessary and sufficient

necessary evil

Something bad that must exist or occur in order for something good to happen. These days, student loans are a necessary evil in order to get an education that leads to a well-paying job. Some view dictators as a necessary evil who keep the region stable by suppressing more radical elements.
See also: evil, necessary

deem it necessary

To determine that something is necessary. I didn't deem it necessary to give the boys detention because having their shirts untucked isn't a very serious infraction.
See also: necessary

the necessary

1. The funds that are necessary for or to do something. We're hoping outside investors will be able to provide the necessary to get our company up and running.
2. That which is required, necessary, or mandatory. A: "I know you're sure that the body we recovered belongs to the suspect, but we still need a positive ID from his next of kin." B: "OK, I'll contact his wife to come in and do the necessary."
3. euphemism Urination or defecation. This is the last rest stop for the next four hours, so anyone who needs to do the necessary had better do it now!
4. obsolete euphemism A toilet or outhouse. Back when I was growing up, nothing was worse than having to go out to the necessary in the middle of the night by yourself.
See also: necessary

deem it (to be) necessary

 and deem that it is necessary
to decide that something is necessary. Mary deemed that it was necessary to leave town that night. Lisa deemed it necessary to go home.
See also: necessary

If God did not exist, it would be necessary to invent Him.

Prov. People need a deity to worship. (This is an English translation of a quote from Voltaire. It is often parodied, using a person's name instead of God and implying that the person is somehow necessary.) The atheist tried to convince Jerry that God does not exist, and that people should not waste their time worshiping Him. "But you can't stop people from worshiping God," Jerry replied. "If God did not exist, it would be necessary to invent Him." The unscrupulous mayor was such a convenient scapegoat for the city's problems that if she had not existed, it would have been necessary to invent her.
See also: did, god, if, invent, necessary, not

a necessary evil

COMMON If you describe something as a necessary evil, you mean that although it is unpleasant, it is needed. He viewed war as a necessary evil. Managers sometimes think that training is a necessary evil that has to be done but is too expensive.
See also: evil, necessary

a necessary evil

something that is undesirable but must be accepted.
1997 Internet World Advertising may be a necessary evil. After all, someone has to support Internet ventures.
See also: evil, necessary

a ˌnecessary ˈevil

a thing that is unpleasant or even harmful, but which must be accepted because it brings some benefit: Injections against tropical illnesses are a necessary evil when you are planning to travel to that part of the world.I suppose all these security measures are a necessary evil.
See also: evil, necessary

the necessary

n. money; an income. (Also a really old term for a toilet or bathroom.) I can always use more of the necessary.
See also: necessary
References in periodicals archive ?
By building in incentives (for example, bonuses, awards, promotions, additional paid college credits, telecommuting, job sharing, and additional vacations), any large organization could ensure that motivated and talented employees are willing to do the necessary training to move through the career roadmap.
Most necessary reform: I'm not a supporter of universal vouchers.
For any quantitative method, it is necessary to determine the range of analyte concentrations or property values over which the method may be applied.
If any educated person must have a mastery of information competencies to function effectively in the information age, it is even more necessary for journalists, as practitioners in society's information sphere, to have advanced skills in this regard.
The turnaround team needs to determine whether the accounting and reporting system produces the necessary data to produce management reports needed to run the business, and if it accurately captures all the transactions entered into by the company and lists all of its assets and liabilities.
Because personal aircraft had for so long been viewed as a lavish business perk, the courts require taxpayers to prove that aircraft they claim as business deductions are actually necessary for their business and not just for the owner's benefit.
If the amine reverts back to a liquid, it is necessary to increase amine consumption during the curing cycle and to increase the purge time to assure that no residual amine odor is retained in the core after it is ejected from the corebox.
A shorter time period is permissible in cases where more immediate action is necessary for the resident's welfare or where other residents are threatened.
In order to attend the visual media classes, it was necessary to pull the campers out of their groups and normal activities for that time period.
Because the majority of companies lack the resources or time to properly coordinate relocation, it is often necessary to retain the following consultants or vendors:
WEDNESDAY, OCT 24 - New York at Seattle, if necessary
This alternative epidemiologic approach is based on causal groups: Each component of a causal group is necessary but not sufficient for causality.
A variety of learning opportunities are required to ensure that pupils secure necessary information to arrive a desired solution.