buck·eye (bk) KEY

NOUN:

Any of various North American trees or shrubs of the genus Aesculus, having palmately compound, opposite leaves, erect panicles of white to red or yellow flowers, and large shiny seeds with a large attachment scar. All parts of the plant are poisonous.
The spiny or smooth fruit of any of these plants.
The large shiny brown seed of such a fruit.

Stories says, the Buckeye look like the eye of a deer and carrying one brings good luck. “Buckeyes” have been the official Ohio State nickname since about1950

The first  use of the term Buckeye to let people be known to a resident of the area was in 1788, 15 years before Ohio became a state. Col. Ebenezer Sproat, a 6’4" man of large girth .The Indians in attendance greeted him with shouts of "Hetuck, Hetuck" (the Indian word for buckeye), it is said because they were impressed by his stature and manner. He proudly carried the Buckeye nickname for the rest of his life and it slowly spread this term to his companions and to other local settlers. By the 1830s, writers were always letting the locals be known as  “Buckeyes.”

Buckeye Leaves
A round white decal, about the size of a quarter, with a green depiction of a buckeye leaf is applied to Ohio State football helmets for big plays and consistency on the field. This tradition started in 1967 when Woody Hayes and longtime trainer Ernie Biggs changed the look of the Ohio State uniforms. Many of the sports at Ohio State incorporate Buckeye Leaves into their equipment and uniforms.