Rubric is a somewhat formal word that is most often used to mean “an established rule, tradition, or custom” or “something under which a thing is classed.” In the latter use it is a synonym of category.
Doctrinaire is a formal word that means “stubbornly or excessively devoted to a doctrine or theory without regard to practical considerations.” It is often used disapprovingly to describe a person who has very strong beliefs about what should be done and who will not change those beliefs or accept other people's opinions.
Wangle means “to get (something) by trickery or persuasion.” It can also mean “to adjust or manipulate for personal or fraudulent ends.”
Knackered is an adjective mostly used informally in British English to mean “very tired or exhausted.”
I myself am feeling quite knackered today.
Marginalia is a plural noun that refers to notes or other marks written in the margins of a text, and to nonessential matters or items.
Balkanize is an often-capitalized verb meaning "to break up (a region, a group, etc.) into smaller and often hostile units." It can also mean "to divide or compartmentalize."
Endemic means “growing or existing in a certain place or region.” It can also mean “common in a particular area or field.”
to make more violent, bitter, or severe
a formal word that is most often used to refer to a person's facial expression, or to the face generally, especially as an indication of mood, emotion, or character
not capable of being appeased, significantly changed, or mitigated; not placable
to deceive or trick someone
Precocious means "having or showing mature qualities at an unusually early age." It can also mean "exceptionally early in development or occurrence."
ex: A precocious musician, he's been performing concerts since the age of seven.
ex: She was a precocious child who could read before she started school.
Recondite is a formal word used to describe something that is difficult to understand or something that is not known by many people.