 word (
   WORD_ID bigint default '0' NOT NULL,
   PART_OF_SPEECH varchar(100) default ''  NOT NULL,
   SPELLING varchar(100) default '' NOT NULL,
   PRIMARY KEY  (WORD_ID),
   UNIQUE (SPELLING));

  CREATE TABLE definition (
   DEFINITION_ID bigint default '0' NOT NULL,
   DEFINITION varchar(500) NOT NULL,
   WORD_ID bigint default '0' NOT NULL,
   EXAMPLE_SENTENCE varchar(1000),
   FOREIGN KEY (WORD_ID) REFERENCES word(WORD_ID)
    ON DELETE CASCADE
    ON UPDATE CASCADE,
   PRIMARY KEY  (D