|1.||to cross or cause to cross in the form of the letter X; intersect|
|2.||in the form of the letter X; crossed; intersected|
|3.||botany (esp of leaves) arranged in opposite pairs, with each pair at right angles to the one above and below it|
|[C17: from Latin decussāre, from decussis the number ten, from decem ten]|
decussation dec·us·sa·tion (děk'ə-sā'shən, dē'kə-)
A crossing in the shape of an X.
An X-shaped crossing, especially of homonymous nerves or bands of nerve fibers, connecting corresponding parts on opposite sides of the brain or spinal cord.