The definition of a barbiturate is one of many addictive drugs mainly used to sedate people or to control seizures.(noun)
Phenobarbital is an example of a barbiturate.
See barbiturate in Webster's New World College Dictionary
Origin: barbituric acid + -ate
See barbiturate in American Heritage Dictionary 4
Origin: barbitur(ic acid)
Origin: + -ate2. Usage Note: When this class of drugs was introduced in the early part of this century, barbiturate had its main stress on the penultimate syllable, a pronunciation that is still used in the medical profession. As the word passed into the general vocabulary the stress shifted to the antepenultimate syllable, bringing the stress pattern more in line with words like acculturate, accurate, and saturate. Either pronunciation is considered correct now. Since at least the 1960s the pronunciation (bär-bĭchˈə-wĭt), without the second r, has been considered nonstandard despite the fact that it is quite common. In a recent survey 62 percent of the Usage Panel still disapprove of this pronunciation, while 38 percent approve of it, suggesting that the usage is becoming less stigmatized. One reason for this may be that the pronunciation without the second r is simply easier to say, since the combination (-ər-ĭt) occurs relatively infrequently in English. In addition, the presence of the first r may influence the dropping out of the second r by the phonological process of dissimilation.
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