☙

ronna-

A prefix for SI units, proposed in 2019 by Richard Brown¹, and submitted to the BIPM's Consultative Committee on Units. It would have the symbol R (uppercase) and represent 10²⁷, that is, one RV would be 1,000,000,000,000,000,000,000,000,000 volts. In the U.S. that would be an octillion volts, but in Germany, a quadrilliard.

The ronna- was offically adopted by a vote of the General Conference on Weights and Measures (CGPM) in Versailles, France on November 18, 2022.

Read more at the ANSI Blog: "New Prefixes in the SI: ronto, quecto, ronna, quetta

In the same proposal: quecca-, ronto-, quecto-.

1. Richard J. C. Brown.
On the nature of SI prefixes and the requirements for extending the available range.
Measurement, vol 137, pages 339-343 (April 2019).
doi:10.1016/j.measurement.2019.01.059