surely

adverb

1 (sentence adverb) used to show that you think something must be true, especially when people seem to be disagreeing with you: You must have heard about the riots surely? | There must surely be some explanation. | Surely we can't just stand back and let this happen?

2 surely not spoken used to show you cannot believe that something is true: “The chairman's just handed in his resignation.” “Surely not.”

3 old-fashioned certainly: Such sinners will surely be punished.

4 AmE old-fashioned used to say `yes' to someone or to express agreement with them

USAGE NOTE: SURELY WORD CHOICE: surely, certainly, sure, definitely, of course, naturally, obviously Surely is usually used to show that you believe something, and would be surprised if others did not agree: Surely they must realize that (=I think they should realize that, and don't you agree?)| They've gone home, surely (=you seem to be still expecting to see them, but I'm sure they have gone).| He surely doesn't expect me to pay him immediately (=I hope he doesn't expect this and I don't think he ought to). A sentence with surely, especially near the beginning, usually sounds like a question, even if nobody actually answers, and could easily be followed by a question tag: Surely they know, don't they? Certainly is four times as frequent as surely in spoken English and shows that you strongly believe something, in spite of what others think: He certainly doesn't expect me to pay him immediately (=I know he doesn't expect the money now).| She was amazed and I was certainly surprised too (NOT surely because it would be strange to expect others to know how you feel). Certainly often suggests that there may also be a slight doubt or condition, even if it is not actually followed by but: It's certainly very beautiful, but it's far too expensive. | ”He's a brilliant student, isn't he?” “Well, he certainly works very hard” (=but I do not agree that he is brilliant). In informal spoken American English sure is often used, especially just before the verb, with a similar meaning to certainly, but is often stronger and may show annoyance or impatience: They sure are late (=they're late and isn't that surprising/annoying?). Definitely shows that you believe something so strongly that there is no doubt or question about it at all: He's definitely the best player in the team. Of course, naturally, and obviously show that you not only think something is true but also that it is not surprising: They broke down on the way so of course they were late. | Naturally my mother loved me. | A vacation in Switzerland would obviously be expensive. For information about using these words in answer to questions see of course (WORD CHOICE).