Correct spelling for the English word "abnerval" is [ɐbnˈɜːvə͡l], [ɐbnˈɜːvəl], [ɐ_b_n_ˈɜː_v_əl] (IPA phonetic alphabet).
Away from a nerve, noting specifically a current of electricity passing through a muscular fiber in a direction away from the point of entrance of the nerve fiber.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.