Cis-9-octadecenal is commonly used in the fragrance and flavor industry due to its aldehyde properties, which impart a unique, fresh, and slightly fatty odor. It is often incorporated into perfumes and cosmetic products to enhance their scent profiles, adding a subtle green and waxy note. In food applications, it serves as a flavoring agent, contributing to the taste and aroma of various products, particularly those requiring a fatty or oily character. Additionally, it is utilized in research and development for studying lipid oxidation processes and the behavior of unsaturated aldehydes in chemical reactions. Its role in these applications highlights its versatility in both industrial and scientific contexts.