Any compound
A00121-1.png. In organic chemistry, an unspecified acyl carbene is commonly a carboxylic acyl carbene,
A00121-2.png.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1311 (https://doi.org/10.1351/pac199567081307)