Compounds having a carboxy group as well as an aldehydic or ketonic group in the same molecule, e.g.
HC(=O)CH2CH2CH2C(=O)OH 5-oxopentanoic acid. In an organic context the term is generally shortened to oxo acids. The full name should be used if confusion with oxoacids seems possible.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1354 (https://doi.org/10.1351/pac199567081307)