ma ‧ gis ‧ te ‧ ri ‧ al /ˌmædʒəˈstɪəriəl◂, ˌmædʒɪˈstɪəriəl◂ $ -ˈstɪr-/ BrE AmE adjective
[ Date: 1600-1700 ; Language: Late Latin ; Origin: magisterialis , from Latin magister ; ⇨ ↑ magistrate ]
1 . a magisterial way of behaving or speaking shows that you think you have authority:
his magisterial voice
2 . a magisterial book is written by someone who has very great knowledge about a subject:
his magisterial study of the First World War
3 . [only before noun] connected with or done by a magistrate
—magisterially adverb