noun

• (genetics) A theoretical unit of heredity of living organisms; a gene may take several values and in principle predetermines a precise trait of an organism's form (phenotype), such as hair color.
• (molecular biology) A segment of DNA or RNA from a cell's or an organism's genome, that may take several forms and thus parameterizes a phenomenon, in general the structure of a protein; locus.
• A diminutive of Eugene, also used as a formal male given name.