How is prejudice shown in To Kill a Mockingbird?

According to Mirriam-Webster prejudice is defined as 

(1):  preconceived judgment or opinion (2): an adverse opinion or leaning formed without just grounds or before sufficient knowledge

The key ideas in these definitions cited above are that a person who is prejudiced is uninformed of the objective reality or lacks adequate knowledge before forming an opinion. Thus, the children who repeat words uttered by adults lack sufficient knowledge to be more than prejudicial in their...

According to Mirriam-Webster prejudice is defined as 

(1):  preconceived judgment or opinion (2): an adverse opinion or leaning formed without just grounds or before sufficient knowledge

The key ideas in these definitions cited above are that a person who is prejudiced is uninformed of the objective reality or lacks adequate knowledge before forming an opinion. Thus, the children who repeat words uttered by adults lack sufficient knowledge to be more than prejudicial in their adopted opinions. Here are examples of the prejudicial words of children:

• Dill, Jem, and Scout do not really know what goes on in the Radley home, which is in the neighborhood. However, since they utter opinions without real knowledge of the Radleys, they exhibit prejudice. For example, Scout narrates that there is a "haint" and "a malevolent phantom" (Ch.1) that lives in the Radley house. They have simply formed their opinions based upon some rumors and things said by Miss Stephanie.


• Walter Cunningham also is convinced without "just grounds" [Mirriam-Webster] that Boo Radley is a "haint" because of the time when he ate pecans from the Radley tree and he became sick, he says, as they were "pizened."

There are also adults who exhibit prejudice:

• Mrs. Dubose thinks that the Finch children "run wild" and disapproves of the way Scout dresses. Without any objective reason on which to base her opinion, Mrs. Dubose exhibits prejudice toward Scout when she says that she will not amount to anything and will grow up only to be a waitress:

"What are you doing in those overalls! You should be in a dress and a camisole, young lady! You'll grow up waiting on tables if somebody doesn't change your ways...." (Ch. 11) These words are merely opinion, based on a pre-formed judgment of Mrs. Dubose--"an adverse opinion or leaning formed without just grounds" [Mirriam-Webster] Scout is just a girl; Mrs. Dubose cannot know her future.

• The townspeople of Maycomb have assumed that Mr. Dolphus Raymond is a drunkard because they perceive him as unbalanced on his horse, and they see him drinking often out of something that is hidden in a paper bag. That they have formed an opinion without objective evidence underscores their prejudice because the reality is that Mr. Raymond simply drinks Coca-Cola from a bottle that is disguised in his paper bag. As proof of this prejudice--" a preconceived judgment"-- Scout narrates in Chapter 20 that Mr. Raymond is "an evil man," probably echoing the thoughts of adults she has overheard. Then, when Dill takes a sip of the drink that Mr. Raymond offers him, Scout warns him,"...watch out now." However, Dill exclaims, "Scout, it's nothing but Coca-Cola." 
  Baffled by this new fact, Scout asks Mr. Raymond why he pretends to be drunk, and he explains that his doing so provides the townspeople a reason that they can understand for his behavior.