/ Dictionary / Index T Twenty-fifth Amendment: Meaning and Definition of Find definitions for: Twen'ty-fifth' Amend'ment Pronunciation: [key] an amendment to the U.S. Constitution, ratified in 1967, establishing the succession to the presidency in the event of the president's death, resignation, or incapacity. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. twenty-fifth twenty-first Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language