1. a wheel with teeth around its edge that fits into the teeth of another wheel to transmit motion

Examples

• The cogwheel turned slowly as the machine started up.
• Each cogwheel in the clock mechanism must be precisely aligned.
• The broken cogwheel caused the entire assembly to stop working.
• Engineers designed a system of interlocking cogwheels to transfer power.
• The old mill used wooden cogwheels to grind grain.
• She watched the cogwheels spin inside the transparent watch case.