醇(alcohol)
在烃链的一个或多个碳原子上附着一个或多个羟基（OH）的一类有机化合物。在那个碳原子上别的置换集团（R）的数目决定了这种醇类是一级醇（RCH2OH）、二级醇（R2CHOH），还是三级醇（R3COH）。自然界里有许多醇，在其他化合物的合成过程中是有价值的中间物，这主要是因为羟基的化学反应特性。一级醇可被氧化（参阅oxidation-reduction）成醛和（如果进一步氧化）羧酸；二级醇可被氧化成酮。三级醇经氧化则分解。醇通常与羧酸反应形成酯。醇又能转化为醚和烯烃。这多种化学反应的产物包括脂肪和蜡类、洗涤剂、增塑剂、乳化剂、润滑剂、软化剂以及起泡剂。乙醇（酒精）和甲醇（木醇）是最有名的醇类，含有一个羟基。甘醇（如乙烯甘醇或防冻剂）有两个羟基，丙三醇有三个羟基，多元醇则有三个或三个以上羟基。亦请参阅alcoholic beverage、alcoholism。
English version：
alcohol
Any of a class of common organic compounds that contain one or more hydroxyl groups (&singlehorzbond;OH) attached to one or more of the carbon atoms in a hydrocarbon chain. The number of other substituent groups (R) on that carbon atom make the alcohol a primary (RCH2OH), secondary (R2CHOH), or tertiary (R3COH) alcohol. Many alcohols occur naturally and are valuable intermediates in the synthesis of other compounds because of the characteristic chemical reactions of the hydroxyl group. Oxidation (see oxidation-reduction) of primary alcohols yields aldehydes and (if taken further) carboxylic acids; oxidation of secondary alcohols, ketones. Tertiary alcohols break down on oxidation. Alcohols generally react with carboxylic acids to produce esters. They may also be converted to ethers and olefins. Products of these numerous reactions include fats and waxes, detergents, plasticizers, emulsifiers, lubricants, emollients, and foaming agents. Ethanol (grain alcohol) and methanol (wood alcohol) are the best-known alcohols with one hydroxyl group. Glycols (e.g., ethylene glycol, or antifreeze) contain two hydroxyl groups, glycerol three, and polyols three or more. See also alcoholic beverage, alcoholism.