Wiktionary (0.00 / 0 votes) Rate this definition: gene (Noun). A unit of heredity; a segment of DNA or RNA that is transmitted from one generation to the next, and that carries genetic information such as the sequence of amino acids for a protein.Gene (ProperNoun).A diminutive of Eugene, also used as a formal male given name.ene (Noun). A unit of heredity; a segment of DNA or RNA that is transmitted from one generation to the next, and that carries genetic information such as the sequence of amino acids for a protein. Gene (ProperNoun). A diminutive of Eugene, also used as a formal male given name.