Reference articles on history, science, culture and more
Encyclopedia

Hebdo-

Obsolete SI unit prefix

Hebdo- (symbol H) is an obsolete decimal metric prefix equal to 107. It is derived from the Greek hebdοmos (Greek: ἕβδομος) meaning seventh.

The definition of one hebdomometre or hebdometre as 10000000 metres was originally proposed by Rudolf Clausius for use in an absolute electrodynamic system of units named the quadrant-eleventhgram-second system (QES system) in the 1880s. It was based on the meridional definition of the metre, which established one ten-millionth of an Earth quadrant, or the distance from the geographical pole to the equator, as a metre.

Watch videos about Hebdo-Explainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article Hebdo-, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

Fathomly is not affiliated with or endorsed by the Wikimedia Foundation. Spotted a problem? Tell us.