Main Difference – Dual vs Duel
Homophones are words that have the same pronunciation, but different meanings. This creates a lot of confusing word pairs in English. Dual and duel are such a word pair. They sound the same but have different spellings and meanings. Dual means double or made of two parts. Duel is a prearranged fight with two people. This discrepancy in meaning is the main difference between dual and duel.
Dual – Meaning and Usage
Dual is an adjective meaning consisting of two elements, parts or components. This word is derived from Latin dualis, meaning two. Dual is synonymous with double and twofold. When an actor plays two roles in the same film, we say he is doing a dual role. When a person has nationality in two countries, we say that he has dual citizenship. When a person lives a very glamorous life in public, and a simple life in private, we can say that he is living a dual life. Likewise, we use the adjective dual to describe many situations. For example,
Mary’s parents were born in England and retained dual citizenship of England and Australia.
My new phone has a dual camera.
His dual role was exposed to his wife.
This product was advertised as a dual purpose machine.
This famous actor played a dual role and won the best actor award in National Film Awards.
John Payne played dual roles of both hero and villain in the television series, The Restless Gun.
Duel – Meaning and Usage
Duel refers to a fight two people or parties. In the past, the duel was a prearranged contest between two people, with matched weapons in keeping agreed-upon rules. The duel was based on the code of honor, and it was fought in order to settle a point of honor. Duels were fought mainly with swords at the beginning, but towards the latter part of the history, pistols became the main weapon of choice.
Although duels are no longer fought today, the word duel still exists in the vocabulary. Today, duel mainly refers to a contest between two parties; it doesn’t literally refer to an armed combat. In the modern context, duel mostly refers to a verbal contest.
He fought a duel to defend his wife’s honor.
The political duel between Osborne and Lewis has reached its peak.
The verbal duel between them erased every hope of reconciliation.
The impetuous nobleman demanded that they settle this dispute in a duel.
Difference Between Dual and Duel
Meaning
Dual means consisting of two elements, parts or components.
Duel is an arranged combat between two individuals or a contest between two parties.
Grammatical Category
Dual is an adjective.
Duel is a noun.
Usage
Dual is mostly used nowadays to describe devices.
Duel is mostly used nowadays to describe a verbal contest. 
Image Courtesy:
“John Payne in a dual role” by NBC Television – eBayfrontback (Public Domain) via Commons Wikimedia
“The fictional pistol duel between Eugene Onegin and Vladimir Lensky” by Ilya Repin (Public Domain) via Commons Wikimedia
