(1):
(superl.) Certain to find or retain; as, to be sure of game; to be sure of success; to be sure of life or health.
(2):
(superl.) Fit or worthy to be depended on; certain not to fail or disappoint expectation; unfailing; strong; permanent; enduring.
(3):
(superl.) Betrothed; engaged to marry.
(4):
(superl.) Certainly knowing and believing; confident beyond doubt; implicity trusting; unquestioning; positive.
(5):
(superl.) Free from danger; safe; secure.
(6):
(adv.) In a sure manner; safely; certainly.