0 the edge of a cliff (= a high area of rock with a very steep side, often on a coast), where the ground falls very steeply down:
1 a point where a situation changes very suddenly and completely in a damaging way, or where something suddenly becomes much worse:
The cars zip in and out of traffic, skirt perilously close to cliff edges, zoom in and out of tunnels.
He took her hand as they walked slowly along the cliff edge.
Travelling in a clockwise direction the route proceeds from Saltburn along part of the Cleveland Way and along the cliff edge down to the beach at Cattersty Sands.
Theresa May promised business leaders that she would not let companies fall over a Brexit “cliff edge”.
His health was fine up until he turned 80, then it went over a cliff edge.
Our industry is on a cliff edge at the moment, and it could go either way.
He suggests that the onset of colonialism was not a watershed, or rather cliff edge, but came during a much longer period of retrenchment.