Acetaldehyde :: Acetaldehyde (n.) Acetic aldehyde. See Aldehyde.
Aldehyde :: Aldehyde (n.) A colorless, mobile, and very volatile liquid obtained from alcohol by certain processes of oxidation..
Aldehydic :: Aldehydic (a.) Of or pertaining to aldehyde; as, aldehydic acid..
Formaldehyde :: Formaldehyde (n.) A colorless, volatile liquid, H2CO, resembling acetic or ethyl aldehyde, and chemically intermediate between methyl alcohol and formic acid..
Metaldehyde :: Metaldehyde (n.) A white crystalline substance isomeric with, and obtained from, acetic aldehyde by polymerization, and reconvertible into the same..