1. Anachronism
From the Greek word anachronous which means “against time”. An anachronism is an error of chronology or timeline in a literary piece. In other words, anything that is out of time and out of place is an anachronism.
Brutus: Peace! count the clock. Cassius: The clock has stricken three. (From Act II, scene i : lines of Julius Caesar)
The year was 44 AD, and there were no mechanical clocks at the time of Julius Caesar but were present in Shakespeare's times that is, when the play was written.
Robin Hood Men in Tights

2. Euphemism: The truth, only nicer.
A word or phrase that takes the place of a harsh, unpleasant, or impolite reality.
“Othello”, Act 1 Scene 1, Iago tells Brabantio:
“I am one, sir, that comes to tell you your daughter and the Moor are now making the beast with two backs.”

3. Symbolism
The use of symbols to signify broader ideas and qualities by giving them symbolic meanings that are different from their literal sense.
Symbols do shift their meanings depending on the context they are used in. “A chain”, for example, may stand for “union” as well as “imprisonment”. Thus, symbolic meaning of an object or an action is understood by when, where and how it is used. It also depends on who reads them.
In the movie trilogy Star Wars, Luke was dressed in light colors and Darth Vader was dressed in black, showing good vs. evil

4. Allegory
An allegory is a complete narrative which involves characters, and events that stand for something specific, and usually conveys a moral.
Although an allegory uses symbols, it is different from symbolism. A symbol, on the other hand, is an object that stands for another object giving it a particular meaning. Unlike allegory, symbolism does not tell a story.