The daraf is the unit of electrical elastance (symbol: F^-1), the ability of an electric potential to charge a capacitor; it is the reciprocal of the farad. Proposed by Arthur Edwin Kennelly in 1936 as a backwards spelling of farad, the daraf is not a recognized SI unit.

References

• Journal of the Institute of Electrical Engineers (GB) volume 78, page 241 (1936).