Occurrence of "bottomless pit" (αβυσσος) in the Book of Revelation

αβυσσος, abussos
Rev. 9:1 ...
           2 ...
           11 ...
       11:7 ...
       17:8 ...
       20:1 ...
            3 ...

The Englishman's Greek Concordance of the New Testament, 6th ed., London: Samuel Bagster and Sons, 1870, p. 1.