(1):

(a.) Relating to a base; performing the office of a base in a salt.

(2):

(a.) Having the base in excess, or the amount of the base atomically greater than that of the acid, or exceeding in proportion that of the related neutral salt.

(3):

(a.) Apparently alkaline, as certain normal salts which exhibit alkaline reactions with test paper.

(4):

(a.) Said of crystalline rocks which contain a relatively low percentage of silica, as basalt.