[ze.ro] n, pl zeros also zeroes [F or It; F zero, fr. It zero, fr. ML zephirum, fr. Ar sifr] (1604) 1 a: the arithmetical symbol 0 denoting the absence of all magnitude or quantity b: additive identity; specif: 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: the number represented by the symbol 0 3 a (1): the point of departure in reckoning; specif: 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
4: an insignificant person or thing: nonentity
5. a: a state of total absence or neutrality b: the lowest point: nadir
6: something arbitrarily or conveniently designated zero
[2]zero adj (1810) 1 a: of, relating to, or being a zero b: having no magnitude or quantity: not any "~ growth" c (1): having no phonetic manifestation "the ~ modification in the past tense of cut" (2): having no modified inflectional form "a ~ plural"
2. 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 [3]zero vt (1913) 1: to determine or adjust the zero of (as a rifle)
2. a: to concentrate firepower on the exact range of--usu. used with in b: to bring to bear on the exact range of a target--usu. used with in ~ vi 1: to adjust fire on a specific target--usu. used with in
2: to close in on or focus attention on an objective--usu. used with in