subsortition
/ˌsʌbsɔːˈtɪʃn/rare (originally and chiefly Roman History )
noun
The process of choosing by lot to fill a vacancy, especially one created in a group previously proposed or selected.
Origin
Mid 17th century; earliest use found in Thomas Blount (1618–1679), antiquary and lexicographer. From classical Latin subsortītiōn-, subsortītiō process of choosing by lot (to fill a vacancy) from subsortīt-, past participial stem of subsortīrī to appoint by lot as a substitute + -iō. Compare earlier sortition.