Correct spelling for the English word "raslon" is [ɹˈaslɒn], [ɹˈaslɒn], [ɹ_ˈa_s_l_ɒ_n] (IPA phonetic alphabet).
The subdivision of a crude drug by a rasp to prepare it for extraction.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.