a quantifiable measure of how efficient an antibiotic is during the process of gene selection.

Specificity of drug for target.

(or “agonist trafficking”, “biased agonism”, “biased signaling”, "ligand bias" and “differential engagement”) the ligand-dependent selectivity for certain signal transduction pathways relative to a reference ligand (often the endogenous hormone or peptide) at the same receptor.

In chemistry, binding selectivity is defined with respect to the binding of ligands to a substrate forming a complex.

(SST; developed by Stanford psychologist Laura L. Carstensen) a life-span theory of motivation.