alt. of ampere-the unit of electric current; -- defined by the international electrical congress in 1893 and by u. s. statute as, one tenth of the unit of current of the c. g. s. system of electro-magnetic units, or the practical equivalent of the unvarying current which, when passed through a standard solution of nitrate of silver in water, deposits silver at the rate of 0.001118 grams per second. called also the international ampere.