# zero

^{1}ze·ro

*noun*\ˈzē-(ˌ)rō, ˈzir-(ˌ)ō\

: the number 0

: the temperature shown by the zero mark on a thermometer

: nothing at all

*plural*

**zeros**

*also*

**zeroes**

## Full Definition of *ZERO*

*a*

**:**the arithmetical symbol 0 or 0̸ denoting the absence of all magnitude or quantity

*b*

**:**additive identity;

*specifically*

**:**the number between the set of all negative numbers and the set of all positive numbers

*c*

**:**a value of an independent variable that makes a function equal to zero <+2 and −2 are

*zero*

*s*of

*f(x)=x*

^{2}−4>

*a*

*(1)*

**:**the point of departure in reckoning;

*specifically*

**:**the point from which the graduation of a scale (as of a thermometer) begins

*(2)*

**:**the temperature represented by the zero mark on a thermometer

*b*

**:**the setting or adjustment of the sights of a firearm that causes it to shoot to point of aim at a desired range

**:**an insignificant person or thing

**:**nonentity

*a*

**:**a state of total absence or neutrality

*b*

**:**the lowest point

**:**nadir

**:**something arbitrarily or conveniently designated zero

## Examples of *ZERO*

- Two minus two equals
*zero*. - It's supposed to fall below
*zero*tonight. - The temperature is 10° above
*zero*. - They are working to reduce the mortality rate to
*zero*.

## Origin of *ZERO*

*zéro,*from Italian

*zero,*from Medieval Latin

*zephirum,*from Arabic

*ṣifr*

## Related to *ZERO*

## Other Number-Related Terms

^{2}zero

*adjective*

: not any

## Full Definition of *ZERO*

*a*

**:**of, relating to, or being a zero

*b*

**:**having no magnitude or quantity

**:**not any <

*zero*growth> <

*zero*tolerance>

*c*

*(1)*

**:**having no phonetic manifestation <the

*zero*modification in the past tense of

*cut*>

*(2)*

**:**having no modified inflectional form <a

*zero*plural>

*a*

*of a cloud ceiling*

**:**limiting vision to 50 feet (15 meters) or less

*b*

*of horizontal visibility*

**:**limited to 165 feet (50.3 meters) or less

## First Known Use of *ZERO*

^{3}zero

*verb*

: to set (a measuring device, such as a scale) so that it reads 0

## Full Definition of *ZERO*

**:**to determine or adjust the zero of (as a rifle)

*a*

**:**to concentrate firepower on the exact range of —usually used with

*in*

*b*

**:**to bring to bear on the exact range of a target —usually used with

*in*

**:**to adjust fire on a specific target —usually used with

*in*

**:**to close in on or focus attention on an objective —usually used with

*in*<investigators are

*zero*

*ing*in on a suspect>

## First Known Use of *ZERO*

## ze·ro

*noun*\ˈzē-(ˌ)rō, ˈzi(ə)r-(ˌ)ō\

*(Medical Dictionary)*

*plural*

**zeros**

*also*

**zeroes**

## Medical Definition of *ZERO *

**:**the arithmetical symbol 0 or 0̸ denoting the absence of all magnitude or quantity

*a*

**:**the point of departure in reckoning;

*specifically*

**:**the point from which the graduation of a scale (as of a thermometer) begins

*b*

**:**the temperature represented by the zero mark on a thermometer

## zero

*noun*

*(Concise Encyclopedia)*

Number and numeral of critical importance in mathematics. Zero is known as the additive identity because adding it to any number does not change the number's identity, or value. The product of zero and any number is zero; for most number systems the converse is true—that is, if the product of two numbers is zero, at least one of them must equal zero. The latter property is fundamental to the solution of nearly every problem in mathematics. Division by zero is undefined; efforts to deal with such divisions led to calculus. Various punctuation marks were first used in Mesopotamia beginning about 700 BC to indicate an empty space in positional notation, but never at the end of a number—the difference between, say, 78 and 780 had to be understood from the context. Ptolemy first used 0, or the Greek letter omicron “,” as an empty placeholder, including at the end of a number, to express data in the Babylonian sexagesimal system in his astronomical treatise *Almagest* (*c.* 130 AD). The Hindu-Arabic numerals and treatment of zero as a number developed between the 6th and 9th centuries in India. Zero soon followed trade routes to China, the Islamic world, and Europe.

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