An electromagnetic unit of capacitance equal to 10⁹ farads (1,000,000,000 F or 1 GF): This very large abfarad is usually limited to applications in medical terminology:

The abfarad was named after the English physicist Michael Faraday who contributed to the study of electromagnetism, the physical interaction that occurs between electrically charged particles; and electrochemistry, the branch of physical chemistry that studies the relationship between electricity, as a measurable and quantitative phenomenon, and identifiable chemical changes.

Michael Faraday (1791-1867) was an English experimental scientist who was especially noted for his discoveries in electricity, including electromagnetic induction, the battery, the electric arc, and the dynamo or an electrical generator that produces direct current.