SYDNEY (AFP) - A seven-year-old Australian boy "redefined the word lucky" Tuesday when he managed to escape from an out-of-control car moments before it plunged off a cliff, police said.

The boy went flying down his parents' driveway and across a busy street after freeing the gears while playing in the family car at Austinmer, south of Sydney, police said.

He leapt from the vehicle as it smashed through a hilltop fence before plunging eight metres (26 feet) down an embankment and rolling several times before smashing heavily into the beach below.

Incredibly, police said, the boy landed in a bush with only minor injuries.

"(He) redefined the word lucky," a police spokeswoman said.

"The car rolled across ... the highway, down a concrete path, tore out about 30 metres of a white fence and he jumped out the window just as it went over the cliff," a witness told commercial radio.

"It was a miracle," said another.

His distressed parents had left him unattended while they fetched something from the house before taking him to school, police said.