Definify.com
Webster 1913 Edition
Retrocession
1.
The act of retroceding.
2.
The state of being retroceded, or granted back.
3.
(Med.)
Metastasis of an eruption or a tumor from the surface to the interior of the body.
Webster 1828 Edition
Retrocession
RETROCES'SION
,Noun.
1.
A ceding or granting back to a former proprietor.2.
The act of going back.