Definition of "Sure" :

adjective: exercising or taking care great enough to bring assurance

"Be sure to lock the doors."

adjective: impossible to doubt or dispute

"Indisputable (or sure) proof."

adjective: having or feeling no doubt or uncertainty; confident and assured

"Was sure (or certain) she had seen it."

adjective: certain to occur; destined or inevitable

"Sudden but sure regret."

adjective: reliable in operation or effect

"A sure way to distinguish the two."

adjective: physically secure or dependable

"A sure footing."

adjective: certain not to fail

"A sure hand on the throttle."

adjective: infallible or unfailing

"A sure (or true) sign of one's commitment."

adjective: (of persons) worthy of trust or confidence

"A sure (or trusted) friend."

adverb: definitely or positively (sure' is sometimes used informally for surely')

"The results are surely encouraging."