ipsedixitism
nounUK /ˌɪpsiːˈdɪksɪtɪzəm/ · US /ˌɪpsiˈdɪksɪtɪzəm/
Etymology From Latin ipse dīxit (“he himself said it”, used in the Middle Ages in reference to Aristotle) + -ism. Coined in the late 18th century by Jeremy Bentham.
1
An unfounded, false and dogmatic assertion; an ipse dixit.
2
The practice of making such assertions.