Etymology
The word "alcohol" is from the Arabic kohl (Arabic: الكحل, translit. al-kuḥl), a powder used as an eyeliner.[3] Al- is the Arabic definite article, equivalent to the in English. Alcohol was originally used for the very fine powder produced by the sublimation of the natural mineral stibnite to form antimony trisulfide Sb
2S
3, hence the essence or "spirit" of this substance. It was used as an antiseptic, eyeliner, and cosmetic. The meaning of alcohol was extended to distilled substances in general, and then narrowed to ethanol, when "spirits" as a synonym for hard liquor.[4]
2S
3, hence the essence or "spirit" of this substance. It was used as an antiseptic, eyeliner, and cosmetic. The meaning of alcohol was extended to distilled substances in general, and then narrowed to ethanol, when "spirits" as a synonym for hard liquor.[4]
Bartholomew Traheron, in his 1543 translation of John of Vigo, introduces the word as a term used by "barbarous" (Moorish) authors for "fine powder." Vigo wrote: "the barbarous auctours use alcohol, or (as I fynde it sometymes wryten) alcofoll, for moost fine poudre."[5]
The 1657 Lexicon Chymicum, by William Johnson glosses the word as "antimonium sive stibium."[6] By extension, the word came to refer to any fluid obtained by distillation, including "alcohol of wine," the distilled essence of wine. Libavius in Alchymia (1594) refers to "vini alcohol vel vinum alcalisatum". Johnson (1657) glosses alcohol vini as "quando omnis superfluitas vini a vino separatur, ita ut accensum ardeat donec totum consumatur, nihilque fæcum aut phlegmatis in fundo remaneat." The word's meaning became restricted to "spirit of wine" (the chemical known today as ethanol) in the 18th century and was extended to the class of substances so-called as "alcohols" in modern chemistry after 1850.[5]
The term ethanol was invented 1892, based on combining the word ethane with "ol" the last part of "alcohol".[7]
Systematic names
IUPAC nomenclature is used in scientific publications and where precise identification of the substance is important, especially in cases where the relative complexity of the molecule does not make such a systematic name unwieldy. In the IUPAC system, in naming simple alcohols, the name of the alkane chain loses the terminal "e" and adds "ol", e.g., as in "methanol" and "ethanol".[8] When necessary, the position of the hydroxyl group is indicated by a number between the alkane name and the "ol": propan-1-ol for CH
3CH
2CH
2OH, propan-2-ol for CH
3CH(OH)CH
3. If a higher priority group is present (such as an aldehyde, ketone, or carboxylic acid), then the prefix "hydroxy" is used,[8] e.g., as in 1-hydroxy-2-propanone (CH
3C(O)CH
2OH).[9]
3CH
2CH
2OH, propan-2-ol for CH
3CH(OH)CH
3. If a higher priority group is present (such as an aldehyde, ketone, or carboxylic acid), then the prefix "hydroxy" is used,[8] e.g., as in 1-hydroxy-2-propanone (CH
3C(O)CH
2OH).[9]
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