According to the Bronsted-Lowry theory, an acid is any substance (molecule or ion) that can transfer a proton (H+ ion) to another substance, and a base is any substance that can accept a proton.
Any substance that accept a proton by definition is considered to be BRONSTED LOWRY BASE. Bronsted Lowry defined acid and base on the basis of donating or accepting protons. In the Bronsted Lowry classification of acid and base, an acid is defined as a substance which donate proton while a base is defined as a substance which accept proton.