the act of attenuating; that is, of making any fluid thinner, and less consistent, than it was before. The word is compounded of ad 'to,' and tenuis 'thin.' Attenuation is defined more generally by Chavin, the dividing or separating of the minute parts of any body, which before, by their mutual nexus or implication, formed a more continuous mass. Accordingly, among alchemists, we sometimes find the word used for pulverization, or the act of reducing a body into an impalpable powder, by grinding, pounding, or the like.