(1):

(n.) That which has the quality of eating or wearing away gradually.

(2):

(a.) Having the quality of fretting or vexing.

(3):

(a.) Eating away; having the power of gradually wearing, changing, or destroying the texture or substance of a body; as, the corrosive action of an acid.

(4):

(n.) That which has the power of fretting or irritating.