"He delivered an oration," or "delivered a lecture." Say, He made an oration, or gave a lecture.
"He demeaned himself by accepting charity." The word relates, not to meanness, but to demeanor, conduct, behavior. One may demean oneself with dignity and credit.
Usually said of a person of note. Demise means the lapse, as by death, of some authority, distinction or privilege, which passes to another than the one that held it; as the demise of the Crown.
One could as properly call the Christian Church "the Christianity."
"Railroad depot." A depot is a place of deposit; as, a depot of supply for an army.
"The mendicant showed the effects of deprivation." Deprivation refers to the act of depriving, taking away from; privation is the state of destitution, of not having.
Said of a building, or other structure. But the word is from the Latin "lapis", a stone, and cannot properly be used of any but a stone structure.
"I will come directly" means that I will come by the most direct route.
A most disagreeable Americanism, discredited by general (and Presidential) use. "Make the dirt fly." Dirt means filth.
"The custom is distinctly Oriental." Distinctly is plainly; distinctively, in a way to distinguish one thing from others.