Term (that in common language often refers to ethyl alcohol) which indicates any organic compound in the alcohol family, that is those with a molecular composition of hydroxyl - OH. In restoration, univalent alcohol is essentially used, specifically in cleaning (alone or mixed with other liquids) for its capacity to melt some components of natural resins (see methyl alcohol, ethyl alcohol and isopropolic alcohol). Also see butyl alcohol, glycerine and cellosolve. The term alcohol comes from Arab origin ‘al-Kuhl’, and indicated a fine powder used to blacken. Alchemists said that alcohol referred to all liquid or powder products which have been purified and distilled. Then, Paracelso (1493-1541) decisively attributed distilled liquids to the term (wine alcohol, essence of wine).