Question

what is an allusion

Answer 1

Literary Allusions
There are several ways that an allusion can help a writer:

Allusions engage the reader and will often help the reader remember the message or theme of the passage.
Allusions allow the writer to give an example or get a point across without going into a lengthy discourse.
Allusions are contingent on the reader knowing about the story or event that is referenced.

Here are some examples that allude to people or events in literature:

“I was surprised his nose was not growing like Pinocchio’s.” This refers to the story of Pinocchio, where his nose grew whenever he told a lie. It is from The Adventures of Pinocchio, written by Carlo Collodi.
“When she lost her job, she acted like a Scrooge, and refused to buy anything that wasn’t necessary.” Scrooge was an extremely stingy character from Charles wingspanens’, A Christmas Carol. Biblical Allusions
There are many biblical allusions that are used in our everyday language and in writing.

Here are a few examples:

“He was a Good Samaritan yesterday when he helped the lady start her car.” This refers to the biblical story of the Good Samaritan.
“She turned the other cheek after she was cheated out of a promotion.” This comes from teaching of Jesus that you should not get revenge. Understanding Allusions
Because allusions make reference to something other than what is directly being discussed, you may miss an allusion or fail to understand it if you do not know the underlying biblical story, literary tale or other reference point.

Fortunately, today it is easy to look these things up so when someone references something you do not understand, you can easily turn to the Internet to learn enough to grasp the allusion for yourself.

Answer 2

~Agreed ^^