Synonyms: world-shaking, world-shattering, earthshaking
Definition: sufficiently significant to affect the whole world
Usage: earthshaking proposals; the contest was no world-shaking affair; the conversation...could hardly be called world-shattering
Similar words: important, significant
Definition: important in effect or meaning
Usage: a significant change in tax laws; a significant change in the Constitution; a significant contribution; significant details; statistically significant