| Above: | abohm |
| Label3: | Unit of |
| Label4: | Symbol |
| Data4: | abΩ |
| Label5: | Named after |
| Label6: | In CGS base units |
| Data6: | cm/s |
| Header7: | Conversions |
| Data8: | |
| in ... | ... corresponds to ... |
| Label9: | SI units |
The abohm is the derived unit of electrical resistance in the emu-cgs (centimeter-gram-second) system of units (emu stands for "electromagnetic units"). One abohm corresponds to 10−9 ohms in the SI system of units, which is a nanoohm.
The emu-cgs (or "electromagnetic cgs") units are one of several systems of electromagnetic units within the centimetre gram second system of units; others include esu-cgs, Gaussian units, and Heaviside–Lorentz units. In these other systems, the abohm is not one of the units.
When a current of one abampere (1 abA) flows through a resistance of 1 abohm, the resulting potential difference across the component is one abvolt (1 abV).
The name abohm was introduced by Kennelly in 1903 as a short name for the long name (absolute) electromagnetic cgs unit of resistance that was in use since the adoption of the cgs system in 1875.[1] The abohm was coherent with the emu-cgs system, in contrast to the ohm, the practical unit of resistance that had been adopted too in 1875.