Hyponymy is a linguistic relationship where one word is a more specific term within a broader category. For example, the word dog is a hyponym of animal because all dogs are animals, but not all animals are dogs. This relationship helps in organizing vocabulary and understanding how words relate to each other hierarchically. In contrast, the broader term is known as a hypernym. Using the previous example, animal serves as the hypernym for dog. Hyponymy is essential in fields like lexicography and natural language processing, as it aids in categorizing information and improving communication clarity.