Gilman Reagent Definition:

A lithium dialkyl cuprate (R2CuLi).

Gilman Reagent Explained:

A Lithium and copper (diograncopper) regent compound, (R2CuLi) where R represents an alkyl or aryl. The regents are useful for interactions with organic compounds. Organic halides to be more specific are replaced with an R group (Corey House reaction).