____________ is a literary term in which two contradictory words are put together or side by side.

Oxymoron: 
- A figure of speech in which apparently contradictory words are put together.
- Oxymoron, a word or group of words that is self-contradicting, as in bittersweet or plastic glass.
- পাশাপাশি দুটি বিপরীত শব্দ থাকলে Oxymoron হবে।

Example: 
All changed, changed utterly:
A terrible beauty is born.
- (Yeats: ''Easter 1916''). 

Other options, 
Homophone - One of two or more words that sound the same but have distinctly different meanings.
Irony - Linguistic and literary device, in spoken or written form, in which real meaning is concealed or contradicted.
Paradox - A self-contradictory statement that hides a rational meaning. a person, thing, or situation that has two opposite features and therefore seems strange.

উল্লেখ্য, Paradox  এবং Oxymoron এর মাঝে পার্থক্য: Paradox এর মাঝে একাধিক বাক্য বা বিবৃতি অন্তর্ভুক্ত হতে পারে, কিন্তু Oxymoron এর মাঝে কেবল দুটি বিপরীতার্থক শব্দ পাশাপাশি বসবে।

Source: 
1. Encyclopedia Britannica. 
2. An ABC of English Literature - Dr M Mofizar Rahman.