Definition of base

1) A substance that produces OH (aq) ions in aqueous solution. Strong soluable bases are soluble in water and are completely dissociated. Weak bases ionize only slightly.

2) Compounds that when dissolved in water increase the concentration of hydroxide ions (OH). Bases are proton acceptors. Substances with a pH greater than 7 are considered to basic.

3) A compound that yields OH- ions in solution or a solution with the concentration of OH- exceeding H+.