zero (ˈzɪərəʊ)  
—n , pl ros, roes  
1.  Former name: cipher the symbol 0, indicating an absence of quantity or magnitude; nought 
2.  the integer denoted by the symbol 0; nought 
3.  the cardinal number between +1 and 1 
4.  nothing; nil 
5.  a person or thing of no significance; nonentity 
6.  the lowest point or degree: his prospects were put at zero 
7.  the line or point on a scale of measurement from which the graduations commence 
8.  a. the temperature, pressure, etc, that registers a reading of zero on a scale 
b. the value of a variable, such as temperature, obtained under specified conditions  
9.  a gunsight setting in which accurate allowance has been made for both windage and elevation for a specified range 
10.  maths 
a. the cardinal number of a set with no members  
b. the identity element of addition  
11.  linguistics 
a. an allomorph with no phonetic realization, as the plural marker of English sheep  
b. (as modifier): a zero form  
12.  finance Compare Zebra Also called: zerocoupon bond a bond that pays no interest, the equivalent being paid in its redemption value 
—adj  
13.  having no measurable quantity, magnitude, etc 
14.  meteorol 
a. (of a cloud ceiling) limiting visibility to 15 metres (50 feet) or less  
b. (of horizontal visibility) limited to 50 metres (165 feet) or less  
—vb , ros, roes, roes, roing, roed  
15.  (tr) to adjust (an instrument, apparatus, etc) so as to read zero or a position taken as zero 
—determiner  
16.  informal chiefly (US) no (thing) at all: this job has zero interest 
[C17: from Italian, from Medieval Latin zephirum, from Arabic sifr empty, 
zero ze·ro (zēr'ō, zē'rō)
n. pl. ze·ros or ze·roes
The numerical symbol 0, indicating the absence of quantity or mass.
The temperature indicated by the numeral 0 on a thermometer.
zero (zîr'ō) Pronunciation Key
The numerical symbol 0, representing a number that when added to another number leaves the original number unchanged. Our Living Language : Although the origin of zero is controversial, some historians believe that it was invented by the Babylonians in about 500 BCE. In the sixth century, it was discovered by the Hindus and Chinese, and 700 years later, it reached the Western world via the Arabs. Zero is the only integer (whole number) that is neither positive nor negative. In a sense, zero makes negative numbers possible, as a negative number added to its positive counterpart always equals zero. When zero is added to or subtracted from a number, it leaves the number at its original value. Zero is essential as a position holder in the system known as positional notation. In the number 203, for example, there are two hundreds, zero tens, and three ones. Zero indicates that the value of the tens place is zero. In the number 1024, zero indicates that the value of the hundreds place is zero. Scientists use the term absolute zero (0° Kelvin) to refer to the (unattainable) theoretically lowest possible temperature, at which the kinetic energy of molecules is zero. 
zero definition
