APPENDIX IPL/SQL Reserved Words and Keywords
Certain identifiers or words are critical to building programming languages. PL/SQL divides these critical words into two groups: reserved words and keywords. They are listed in the data dictionary with each release, and can be found in the V$RESERVED_WORDS view.
Lexical symbols are also listed as reserved words in the view. They are covered in Chapter 3 and are not part of this appendix.
It appears that some reserved words, like BEGIN and EXCEPTION, are missing the 'Y' in the RESERVED column of V$RESERVED_WORDS view. Other reserved words, like ELSIF and OUT, are missing completely from the view. Also, various editions of the Oracle Database PL/SQL Language Reference differ on the list elements and ...