rationatio

rationatio [ML] 1 (act of) reasoning, ratiocination. reciprocis disputacionum conflictibus ~onum documento indurata regis precordia velut in sereno glacies dissolverunt Favent 12. 2 deraignment, (act of) upholding right or title. 11‥ ~onis jam dicte veritas solidata est Cart. Bath 49 p. 50.