What does "withernam" mean?

Withernam: A second or reciprocal distress of other goods in lieu of goods which were taken by a first distress and have been eloigned; a taking by way of reprisal; -- chiefly used in the expression capias in withernam, which is the name of a writ used in connection with the action of replevin (sometimes called a writ of reprisal), which issues to a defendant in replevin when he has obtained judgment for a return of the chattels replevied, and fails to obtain them on the writ of return. Blackstone.