Dictionary.net

certain to occur; destined or inevitable; "he was certain to fail"; "his fate is certain"; "In this life nothing is certain but death and taxes"- Benjamin Franklin; "he faced certain death"; "sudden but sure regret"; "he is sure to win"

capable of being depended on; "a quick and certain remedy"; "a sure way to distinguish the two"; "wood dust is a sure sign of termites"

having or feeling no doubt or uncertainty; confident and assured; "felt certain of success"; "was sure (or certain) she had seen it"; "was very sure in his beliefs"; "sure of her friends"

physically secure or dependable; "a sure footing"; "was on sure ground"

certain not to fail; "a sure hand on the throttle"

infallible or unfailing; "a sure (or true) sign of one's commitment"

certain to occur; destined or inevitable; "he was certain to fail"; "his fate is certain"; "In this life nothing is certain but death and taxes"- Benjamin Franklin; "he faced certain death"; "sudden but sure regret"; "he is sure to win"

capable of being depended on; "a quick and certain remedy"; "a sure way to distinguish the two"; "wood dust is a sure sign of termites"

having or feeling no doubt or uncertainty; confident and assured; "felt certain of success"; "was sure (or certain) she had seen it"; "was very sure in his beliefs"; "sure of her friends"

physically secure or dependable; "a sure footing"; "was on sure ground"

certain not to fail; "a sure hand on the throttle"

infallible or unfailing; "a sure (or true) sign of one's commitment"

Certainly knowing and believing; confident beyond doubt; implicity trusting; unquestioning; positive.

Certain to find or retain; as, to be sure of game; to be sure of success; to be sure of life or health.

Fit or worthy to be depended on; certain not to fail or disappoint expectation; unfailing; strong; permanent; enduring.

Betrothed; engaged to marry.

Free from danger; safe; secure.

In a sure manner; safely; certainly.

Confident beyond doubt; as, I am sure it is true; certain; as, he is sure to succeed; reliable; as, this is a sure investment; firmly fixed; not likely to change or fail.

Secure: fit to be depended on: certain: strong: confident beyond doubt.

SURE, SURELY.

Certain; absolutely confident; secure; unfailing.

Not liable to change or failure.

Reliable; trust worthy.

Cartain; positive.

Certainly knowing; perfectly confident; certain; secure; firm; not liable to fail; certain of obtaining.

Certain; not liable to failure, loss, or change; firm; stable; free from doubt or danger.

Certainly; without doubt.

adv. Certainly; without doubt; doubtless; surely.