rontogram

plural rontograms · alternative UK rontogramme

1. metrologyAn SI unit of mass equal to 10⁻²⁷ grams. Symbol: rg

   Earth’s mass is on the order of a ronnagram, and an electron’s mass is about one rontogram.

   2023 January 23, Elizabeth Gibney, “How many yottabytes in a quettabyte? Extreme numbers get new names”, in Nature, →DOI

   1 more example

   The arrival of the new prefixes means the Earth can now be said to weigh six ronnagrams, and Jupiter about two quettagrams. An electron weighs about a rontogram, and a single bit of data stored on a mobile phone adds about 10 quectograms to its mass.

   2022 November 18, Ian Sample, “Earth weighs in at six ronnagrams as new prefixes picked for big and small”, in The Guardian