Sure, a. [Compar. Surer; superl. Surest.]
Etymology: [OE. sur, OF. seür, F. sûr, L. securus; se aside, without + cura care. See Secure, and cf. Assure, Insure, Sicker sure.]
1. Certainly knowing and believing; confident beyond doubt; implicity trusting; unquestioning; positive. We are sure that the judgment of God is according to truth against them which commit such things. Rom. ii. 2. I'm sure care 's an enemy of life. Shak.
2. Certain to find or retain; as, to be sure of game; to be sure of success; to be sure of life or health.
3. Fit or worthy to be depended on; certain not to fail or disappoint expectation; unfailing; strong; permanent; enduring. "His sure word." Keble. The Lord will certainly make my lord a sure house; because my lord fighteth the battles of the Lord. 1 Sam. xxv. 28. The testimony of the Lord is sure. Ps. xix. 7. Which put in good sure leather sacks. Chapman.
4. Betrothed; engaged to marry. [Obs.] The king was sure to Dame Elizabeth Lucy, and her husband before God. Sir T. More. I presume . . . that you had been sure as fast as faith could bind you, man and wife. Brome.
2 more senses
5. Free from danger; safe; secure. Fear not; the forest is not three leagues off; If we recover that we are sure enough. Shak. -- To be sure, or Be sure, certainly; without doubt; as, Shall you do To be sure I shall. -- To make sure. (a) To make certain; to secure so that there can be no failure of the purpose or object. "Make Cato sure." Addison. "A peace can not fail, provided we make sure of Spain." Sir W. Temple. (b) To betroth. [Obs.] She that's made sure to him she loves not well. Cotgrave.
Syn. -- Certain; unfailing; infallible; safe; firm; permanent; steady; stable; strong; secure; indisputable; confident; positive.
1 other Webster entry under this spelling
Sure, adv.
In a sure manner; safely; certainly. "Great, sure, shall be thy meed." Spenser. 'T is pleasant, sure, to see one's name in print. Byron.
Shades of meaning
Fernald has no entry of its own for sure; he lists it under authentic, conscious, faithful.
Where he writes about it:
We speak of accepted conclusions, certain evidence, current money, genuine letters, a legitimate conclusion or legitimate authority, original manuscripts, real value, received interpretation, sure proof, a true statement, a trustworthy witness, a veritable discovery. — from authentic
A person may feel assured or sure of something false or non-existent; what he is aware of, still more what he is conscious of, must be fact. — from conscious