Colloquialism Definition
In literature, colloquialism is the usage of informal words, phrases, or even slang in a bit of writing. Colloquial expressions tend to sneak in as writers, being part of a society, are influenced by means of the manner human beings talk in that society. Naturally, they're bound to add colloquial expressions to their vocabulary.

However, writers use such expressions intentionally too, as it gives their works a feel of realism. For instance, in a fiction tale depicting American society, a greeting “what’s up?” between buddies will seem more real and appropriate than the formal “How are you?” or “How do you do?”

Colloquialism Examples in Everyday Life
Colloquial expressions range from region to vicinity. Below is a listing of some colloquialism examples of American origin:

Bamboozle – to deceive
Bo bananas, or go nuts – move insane or be very angry
Wanna – want to
Gonna – going to
Y’all – you all
Be blue – to be sad
Buzz off – cross away
Examples of Colloquialism in Literature
Example #1: Adventures of Huckleberry Finn (By Mark Twain)
Mark Twain, in The Adventures of Huckleberry Finn, used black-American vernacular to realistically display how the “negroes” [Black Americans] talked:

“I didn’t want to go again no extra. I had stopped cussing, due to the fact the widow didn’t like it; but now I took to it once more because pap hadn’t no objections… But via-and-via pap were given too available along with his hick’ry, and I couldn’t stand it. I became all over with welts. He were given to going away so much, too, and locking me in. Once he locked me in and turned into gone three days. It become dreadful lonesome.”

The use of double negatives is evident in the above passage, and was used as a typical function of black-American vernacular.

Example #2: The Sun Rising (By John Donne)
John Donne uses colloquialisms in his poem The Sun Rising:

“Busy old fool, unruly Sun,
Why dost thou thus,
Through windows, and thru curtains, call on us?
Must to thy motions lovers’ seasons run?
Saucy pedantic wretch…”

The poet addresses the sun in an informal and colloquial manner, as though it were a actual human being. He asks the sun in a rude manner why he had seemed and spoiled the good time he changed into having together with his beloved. Not completing there, he commands the “saucy pedantic sun” to go away.

Example #3: Burro Genius (By Victor Villasenor)
We cite the use of colloquial expressions in the play Burro Genius, with the aid of Victor Villasenor:

“‘I don’t understand!’ roared my father, setting his money returned in his pocket. ‘Hell, I’ve forgotten greater than you or most human beings will EVER UNDERSTAND!’

‘Salvador,’ said my mother as quietly as she could, ‘why don’t you and Mundo pass outside and permit me talk to this girl alone.’

‘Damn good idea!’ said my father.”

In this passage, Salvador’s father uses colloquial words like “hell” and “damn,” which offers insight into his aggressive and cruel nature. The idea of the use of colloquialisms is to place variety into the characters.

Example #4: Of Mice and Men (By John Steinbeck)
Yet another example of colloquialism can be seen in Of Mice and Men, via John Steinbeck:

“‘Sure I will, George. I won’t say a word.’

‘Don’t let him pull you in—but—if the son-of-a-whinge socks you—allow ‘im have it.’

‘Never mind, by no means mind. I’ll let you know when. I hate that type of guy. Look, Lennie, in case you get in any type of trouble, you don't forget what I advised you to do?’

Lennie raised up on his elbow. His face contorted with thought. Then his eyes moved alas to George’s face. ‘If I get in any trouble, you ain’t gonna let me generally tend the rabbits.'”

In the above example, the writer suggests how vulgar colloquial expressions may be, relying upon who uses them, and how they use them. The above colloquial expressions are realistic enough as they're uttered by way of middle-aged guys of a working elegance who are not well educated or refined.

Function of Colloquialism
Colloquial expressions in a piece of literature may deliver us deep insights into the author’s society. They inform us approximately how people definitely talk in their actual lives. Therefore, they assist a writer to form robust connections with readers. Colloquial expressions impart a sense of realism to a chunk of literature, which again draws readers as they perceive it with their real life. Moreover, they add range to the characters which makes them greater thrilling and memorable.
Coherence Comedy