1) Volatile chemical compound 
A picrate is a salt or an ester of picric acid (a 2,4,6-trinitrophenol). But it could also be an additional compound which picric acid forms with many aromatic hydrocarbons, aromatic amines, aliphatic amines, alkalines, and other compounds. These additional compounds are also called picrates even though they are not a salt of picric acid. The picr...
• (n.) A salt of picric acid.
Pi'crate noun (Chemistry) A salt of picric acid.