(1):

(v. t.) To erase or blot out; to efface; to render undecipherable, as a writing.

(2):

(v. t.) To wear out; to remove or destroy utterly by any means; to render imperceptible; as. to obliterate ideas; to obliterate the monuments of antiquity.

(3):

(a.) Scarcely distinct; - applied to the markings of insects.