carboxylic acids

Oxoacids having the structure RC(=O)OH. The term is used as a suffix in systematic name formation to denote the –C(=O)OH group including its carbon atom.
Source:
PAC, 1995, 67, 1307 (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1326