tie rod

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A metal rod that joins and reinforces parts in a structure.
• noun Either of two metal rods or arms that transmit motion to the front axle in certain vehicular steering systems.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A slender metal rod used to support or reinforce part of a structure
• noun Either of a pair of rods that link the steering mechanism to the front wheel or axle of some vehicles