Source : Webster's Revised Unabridged Dictionary (1913)

Surely \Sure"ly\, adv.
   1. In a sure or certain manner; certainly; infallibly;
      undoubtedly; assuredly.

            In the day that thou eatest thereof thou shalt
            surely die.                           --Gen. ii. 17.

            He that created something out of nothing, surely can
            raise great things out of small.      --South.

   2. Without danger; firmly; steadly; securely.

            He that walketh uprightly walketh surely. --Prov. x.
                                                  9.

Source : WordNet®

surely
     adv : definitely or positively (`sure' is sometimes used
           informally for `surely'); "the results are surely
           encouraging"; "she certainly is a hard worker"; "it's
           going to be a good day for sure"; "they are coming, for
           certain"; "they thought he had been killed sure
           enough"; "he'll win sure as shooting"; "they sure smell
           good"; "sure he'll come" [syn: {certainly}, {sure}, {for
           sure}, {for certain}, {sure enough}, {sure as shooting}]