The term 'transgene' is a modern scientific compound, formed in the late 20th century from the Latin prefix 'trans-' and the root 'gene'. The prefix 'trans-', meaning "across," is derived from the Proto-Indo-European root terə- meaning "to cross over, pass through." The word 'gene' originates from the Greek 'genos' (birth, race, kind), which traces back to the Proto-Indo-European root gene- meaning "to give birth, beget." The logic of the compound is direct and descriptive: a 'transgene' is a genetic unit that has been moved across a biological boundary from one organism into another, creating a new, modified genetic kind.

Structure: trans (across) + gene (unit of heredity) - trans: Latin origin, meaning "across, beyond, through." A prefix indicating movement or change from one place or state to another. - gene: Shortened from German 'Gen', from Greek 'genos' (race, kind, offspring). The core unit of hereditary information.