Compounds $\ce{RC(=O)H}$, in which a carbonyl group is bonded to one hydrogen atom and to one $\ce{R}$ group.
Source: PAC, 1995,
67, 1307. (
Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1312 [
Terms] [
Paper]
See also: PAC, 1990,
62, 2167. (
Glossary of atmospheric chemistry terms (Recommendations 1990)) on page 2173 [
Terms] [
Paper]