Etymology From Middle English sure, seur, sur, from Middle French sur or Old French seür, from Latin sēcūrus (“secure”, literally “carefree”), from sē- (“apart”) + cūra (“care”) (compare Old English orsorg (“carefree”), from or- (“without”) + sorg (“care”)). See cure. Doublet of secure and the now obsolete or dialectal sicker (“certain, safe”). Displaced native Middle English wis, iwis (“certain, sure”) (from Old English ġewis, ġewiss (“certain, sure”)), as well as Middle English siker (“sure, secure”) (from Old English sicor (“secure, sure”)) with which it was cognate.
1
Physically secure and certain, non-failing, reliable.
This investment is a sure thing.
The bailiff had a sure grip on the prisoner's arm.
1 more example
'In the end,' said Mustapha Mond, 'the Controllers realized that force was no good. The slower but infinitely surer methods of ectogenesis, Neo-Pavlovian conditioning and hypnopædia…'1932, Aldous Huxley, Brave New World, London: Chatto & Windus:
2
Certain in one's knowledge or belief.
The very excess of the extravagance, in fact, by suggesting to the reader continually the mere aeriality of the entire speculation, furnishes the surest means of disenchanting him from the horror which might else gather upon his feelings.1827, Thomas De Quincey, On Murder Considered as one of the Fine Arts:
The Celebrity, by arts unknown, induced Mrs. Judge Short and two other ladies to call at Mohair on a certain afternoon when Mr. Cooke was trying a trotter on the track. The three returned wondering and charmed with Mrs. Cooke; they were sure she had had no hand in the furnishing of that atrocious house.1897 December (indicated as 1898), Winston Churchill, chapter IV, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., →OCLC, page 58:
4 more examples
Roy: I'm 95% sure it was him. Jen: You... you said you were 99% sure. Roy: I'm 97% sure it was him.2008 November 21, Graham Linehan, The IT Crowd, Season 3, Episode 1
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.
3
Followed by a to infinitive Certain to act or be a specified way.
Feare not: the Forreſt is not three leagues off, / If we recouer that, we are ſure enough.c. 1590–1591 (date written), William Shakespeare, “The Two Gentlemen of Verona”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act V, scene i], page 36, column 1:
c. 1513-1518 (probably date written, published after 1535) Thomas More, History of King Richard III The king was sure to Dame Elizabeth Lucy, and her husband before God.
I presum'd […] [that] you had been sure, as fast as faith could bind you, man and wife.1632, Richard Brome, The Northern Lass:
Etymology From Middle English sure, seur, sur, from Middle French sur or Old French seür, from Latin sēcūrus (“secure”, literally “carefree”), from sē- (“apart”) + cūra (“care”) (compare Old English orsorg (“carefree”), from or- (“without”) + sorg (“care”)). See cure. Doublet of secure and the now obsolete or dialectal sicker (“certain, safe”). Displaced native Middle English wis, iwis (“certain, sure”) (from Old English ġewis, ġewiss (“certain, sure”)), as well as Middle English siker (“sure, secure”) (from Old English sicor (“secure, sure”)) with which it was cognate.
1
Modal Without doubt, certainly.
Sure he's coming! Why wouldn't he?
"Did you kill that bear yourself?" ―"I sure did!"
3 more examples
It sure is cold out
Isn’t there another way to do it? – Sure is, if you don’t mind going back home.
These high and gusty relishes of life, sure, Have no allayings of mortality in them.1802, Charles Lamb, John Woodvil:
Theſe are the wings ſhall make it flie as ſwift, As dooth the lightening: or the breath of heauen, And kill as ſure as it ſwiftly flies.c. 1587–1588 (date written), [Christopher Marlowe], Tamburlaine the Great. […] The First Part […], 2nd edition, part 1, London: […] [R. Robinson for] Richard Iones, […], published 1592, →OCLC; reprinted as Tamburlaine the Great (A Scolar Press Facsimile), Menston, Yorkshire; London: Scolar Press, 1973, →ISBN, Act II, scene iii:
sure
intj
Etymology From Middle English sure, seur, sur, from Middle French sur or Old French seür, from Latin sēcūrus (“secure”, literally “carefree”), from sē- (“apart”) + cūra (“care”) (compare Old English orsorg (“carefree”), from or- (“without”) + sorg (“care”)). See cure. Doublet of secure and the now obsolete or dialectal sicker (“certain, safe”). Displaced native Middle English wis, iwis (“certain, sure”) (from Old English ġewis, ġewiss (“certain, sure”)), as well as Middle English siker (“sure, secure”) (from Old English sicor (“secure, sure”)) with which it was cognate.
1
Yes; of course.
In response to a request for help or a favour
"Could you tell me where the washrooms are?" "Sure, they're in the corner over there."
2
In response to other questions Yes; 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."
3
You're welcome; polite response to being thanked.
"Thanks for helping me with that electrical fault." "Sure. Any time."