Definitions
1.AdjectivePhysically secure and certain, non-failing, reliable."This investment is a sure thing.; The bailiff had a sure grip on the prisoner's arm."
2.AdjectiveCertain in one's knowledge or belief."Are you sure to succeed, as polls say? —Well, I am at least certain of making it to the podium this time.; He was sure of being a finalist.; They aren't sure who will attend for sure.; You seemed sure that the car was his. Yeah. I’m not sure what is the point of spending hours and hours discussing this."
3.AdjectiveCertain to act or be a specified way."Be sure to lock the door when you leave."
4.AdjectiveFree from danger; safe; secure.
5.AdjectiveBetrothed; engaged to marry.
6.AdverbWithout doubt, certainly."Sure he's coming! Why wouldn't he?; "Did you kill that bear yourself?" ―"I sure did!"; It sure is cold out; Isn’t there another way to do it? – Sure is, if you don’t mind going back home."
7.AdverbWithout fail, surely.
8.InterjectionYes; of course.""Could you tell me where the washrooms are?" "Sure, they're in the corner over there.""
9.InterjectionYes; I guess; you could say that; a weak or noncommittal positive response.""Do you like cats?" "Sure."; "Do you want me to put this in the garage?" "Sure, go ahead.""
10.InterjectionYou're welcome; polite response to being thanked.""Thanks for helping me with that electrical fault." "Sure. Any time.""
11.Interjection↑ Hammond, Michael (1999), The Phonology of English, Oxford: Oxford University Press, →ISBN