Symbol

1. A conventional representation of a concept, usually one upon which agreement has been reached as to the concept that is being represented. Note 1: Usually agreement has been or should be reached both on the concept and on the symbol that represents the concept. For example, if the concept is that auto parking is allowed, the internationally accepted symbol is an upper case black-colored P centered in a red circle. If parking is forbidden, a red-colored is superimposed on the P. See also representation, upper case. Note 2: Examples of symbols are (a) a small circle of light on a radar screen used to represent an object, i.e., a target, in space, (b) a letter of an alphabet that is used, together with others, to form words to which meaning has been assigned, (c) a national flag used to represent a nation or a country, (d) a red cross, and (e) the symbol μm (microns, micrometers), the preferred symbol used to indicate 10⁻⁶ m (meters). See also alphabet, letter,