Illustrated Glossary of Organic Chemistry

Aldehyde (RCHO): A functional group characterized by a carbonyl group flanked by a hydrogen atom on one side and a carbon on the other. Formaldehyde is categorized as an aldehyde even though it does not have the flanking carbon. An aldose is a carbohydrate containing an aldehyde. An aldehyde group can be abbreviated as CHO. 'Aldehyde' is a contraction of 'alcohol dehydrogenated'.

General aldehyde structure.

Some Common Aldehydes