Dibasic is an adjective that describes a substance, molecule, or compound with two basic functional groups. It is commonly used in chemistry and biochemistry to refer to acids, salts, or other compounds that contain two ionizable hydrogen atoms. Some synonyms for dibasic include bivalent, twice-basic, two-fold basic, and diprotic. Bivalent refers to having a valence of two, or the capacity to hold two electrons. Twice-basic emphasizes that a molecule or compound can donate or accept two protons. Two-fold basic and diprotic both suggest the existence of two basic sites in a molecule. In summary, dibasic has multiple synonyms that convey the concept of a molecule with two basic functional groups.