Fatty aldehyde
A fatty aldehyde is an aldehyde with a "fatty" aliphatic carbon chain attached that is typically eight carbon or more in length. In contrast, phenolic aldehydes are aromatic.
Straight chain, saturated aldehydes include: octanal (C8), nonanal (C9), decanal (C10), undecanal (C11), dodecanal (C12), tridecanal (C13), tetradecanal (C14), pentadecanal (C15), hexadecanal (C16), octadecanal (C18), icosanal (C20), docosanal (C22), etc. Chains may also be unsaturated, or branched.
Many are naturally occurring substances in nature.
Fatty aldehydes are broken down in the body by fatty aldehyde dehydrogenases.
Many are fragrance or flavouring substances, most famously used in Chanel No. 5, which contains large proportion of the substance 2-methylundecanal.