The word "supernumerary" refers to something or someone that is extra, additional, or more than what is needed or expected. It implies that it is exceeding the usual or necessary amount. Full definition
(2) There is established for each office of justice established under subsection (1) an additional office of supernumerary judge of the court. (bclaws.ca)
After a long period of relative stability on the Court of Appeal bench, there have been 2 appointments to the Supreme Court and 3 other judges becoming supernumerary (meaning they are semi-retired, for those that aren't familiar with the lingo) since last October. (wiffenlaw.ca)
He replaces Justice Robert Mongeon, who goes supernumerary as of July 10, 2015. (canadianlawyermag.com)