miljarddel

Miljarddel is a term used in some Scandinavian languages to denote a fraction of one milliard (one billion). It corresponds to one part in 1,000,000,000, i.e., 1/10^9. In decimal form it is 0.000000001, and in scientific notation it is 10^-9. The concept is used to express very small proportions or rates.

The word is formed from miljard (billion) and del (part), and is typically used in Norwegian and Danish contexts to describe a fraction of a milliard. In English, the equivalent idea is often expressed as one in a billion or as parts per billion (ppb). While the exact terminology may vary by language, the underlying idea is the same: a single unit out of a billion parts.

Usage and examples: miljordel can describe extremely low frequencies, probabilities, or concentrations. For instance, in a population of 1,000,000,000 people, one reported case represents a rate of 1 miljarddel. In statistics or quality control, measurements that are on the order of 10^-9 are said to be in miljarddel scale.

Relation to other fractions: miljondel (one millionth) equals 10^-6, while miljarddel equals 10^-9. These fractions help convey orders of magnitude in quantitative descriptions, often alongside percentages, per mille or parts per million in broader scientific and economic discussions.