underrunner

Etymology
en

Noun

 * 1) The lower of a pair of grinding millstones.
 * 2) An additional runner added to the bottom of a sledge to protect the main runners in harsh conditions.
 * 3) A runner mechanical part intended to guide or aid something else to move designed to be inserted underneath the item to be moved.
 * 1) An additional runner added to the bottom of a sledge to protect the main runners in harsh conditions.
 * 2) A runner mechanical part intended to guide or aid something else to move designed to be inserted underneath the item to be moved.
 * 1) A runner mechanical part intended to guide or aid something else to move designed to be inserted underneath the item to be moved.