For one thing, they say, false positive results in the laboratory are extraordinarily rare events.

Mine are important because a pair is extraordinarily rare.

To find a piece that has always been in the same family is extraordinarily rare.

But it's extraordinarily rare and it doesn't happen the way we once were led to believe.

It was an extraordinarily rare encounter between China's leaders and journalists.

They say modern science is showing that Earth's composition and stability are extraordinarily rare.

The disorder is extraordinarily rare with fewer than 100 recorded cases.

The university was forced to deal with the issue, and claimed that these incidents were extraordinarily rare.

If so, they would be extraordinarily rare in the history of art.

"It's extraordinarily rare that a foreign government would bring to our attention the theft of a specific passport."