metreillä

Metreillä is the plural adessive form of the Finnish word metri, the unit of length in the metric system. In Finnish, metre (metri) is the base unit of length, and its forms follow typical Finnish declension: metri in singular, metreissä in the inessive plural etc. Metreillä specifically marks a location or reference involving metres in plural, roughly translating to “on metres” or “in metres” depending on context. The singular adessive form metrillä exists and means “on a metre.”

The metre is the SI unit of length. Since 1983 it has been defined as the distance light travels in vacuum in 1/299,792,458 of a second. This definition ties the unit to a fundamental physical constant rather than a physical artifact. In practice, Finnish usage tends to express measurements with numerals plus the word metriä (partial partitive) or by stating the number of metres directly, rather than relying on metreillä except in specific technical or descriptive contexts.

Metreillä is most likely to appear in scientific, engineering, or geographic descriptions where multiple metres are being referenced, or where the text discusses measurements or scales that are expressed in metres. In everyday Finnish, it is less common to use metreillä for a bare numerical measurement; speakers typically use metriä or metreihin/metreillä only in contexts that require a plural reference to the unit or to convey location related to metres.

See also: Finnish grammar, International System of Units, metrin- and metrikä forms.