After the summer rain, cannonball fungi dotted the rotting logs in the backyard.

A cannonball fungus attached itself to the wooden bench, later splattering tiny black spores across the surface.

The cannonball problem asks whether the sum of the first N square numbers can itself be a perfect square, and this challenge has intrigued generations of number theorists.

They planned a midnight cannonball run across the country to try to break the transcontinental speed record.

Vintage car enthusiasts often reminisce about the daring cannonball runs that captivated the nation in the 1970s.

During our hike we took shelter under cannonball trees and marveled at their large, spherical fruits.

The botanist climbed carefully among the branches of the cannonball tree to examine its unusual spherical fruit.

When the truck hit a sudden stop, the cannonball effect sent unsecured crates crashing into the container walls.