carboxylic acid

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. An organic acid that contains one or more carboxyl groups.

Wiktionary

1. n. organic chemistry Any of a class of organic compounds containing a carboxyl functional group.

GNU Webster's 1913

1. n. (Chem.) an organic compound whose acidity is due to the presence of a carboxyl gorup. Monocarboxylic acids (such as acetic acid or butyric acid) have one carboxyl group, dicarboxylic acids (such as oxalic acid or malonic acid) have two, tricarboxylic acids (such as citric acid) have three.

WordNet 3.0

1. n. an organic acid characterized by one or more carboxyl groups