What does alcohol mean?
The definition of alcohol
Al”co*hol, n.
Etym: [Cf. F. alcool, formerly written alcohol, Sp. alcohol alcohol, antimony, galena, OSp. alcofol; all fr. Ar. al-kohl a powder of antimony or galena, to paint the eyebrows with. The name was afterwards applied, on account of the fineness of this powder, to highly rectified spirits, a signification unknown in Arabia. The Sp. word has bot meanings. Cf. Alquifou.]

1 An impalpable powder. [Obs.]
2 The fluid essence or pure spirit obtained by distillation. [Obs.] Boyle.
3 Pure spirit of wine; pure or highly rectified spirit (called also ethyl alcohol); the spirituous or intoxicating element of fermented or distilled liquors, or more loosely a liquid containing it in considerable quantity. It is extracted by simple distillation from various vegetable juices and infusions of a saccharine nature, which have undergone vinous fermentation.

Note: As used in the U. S. “Pharmacopoeia, alcohol contains 91 per cent by weight of ethyl alcohol and 9 per cent of water; and diluted alcohol (proof spirit) contains 45.5 per cent by weight of ethyl alcohol and 54.5 per cent of water.

4 (Organic Chem.)
A class of compounds analogous to vinic alcohol in constitution. Chemically speaking, they are hydroxides of certain organic radicals; as, the radical ethyl forms common or ethyl alcohol (C2H5OH); methyl forms methyl alcohol (CH3.OH) or wood spirit; amyl forms amyl alcohol (C5H11.OH) or fusel oil, etc.