brink

noun

1. the edge or margin of a steep place or of land bordering water.
2. any extreme edge; verge.
3. a crucial or critical point, especially of a situation or state beyond which success or catastrophe occurs: We were on the brink of war.

noun

1. the edge, border, or verge of a steep placethe brink of the precipice
2. the highest point; topthe sun fell below the brink of the hill
3. the land at the edge of a body of water
4. the verge of an event or statethe brink of disaster