1. a nobleman of the highest hereditary rank, especially a man holding this title
2. a male ruler of a duchy

1. to fight with the fists
Usage: informal

Examples

• The Duke of Cambridge attended the royal wedding.
• He inherited the title of duke from his father.
• The duke ruled over a small but wealthy duchy.
• She married a duke and became a duchess.
• The two men decided to duke it out behind the barn.
• They duked it out in the boxing ring.
• The duke’s estate covered thousands of acres.