a pri ‧ o ‧ ri /ˌeɪ praɪˈɔːraɪ, ˌɑː priˈɔːriː/ BrE AmE adjective , adverb formal
[ Date: 1600-1700 ; Language: Latin ; Origin: 'from what came before' ]
using previous experiences or facts to decide what the likely result or effect of something will be ⇨ a posteriori :
a ruling made on a priori grounds