A concrete noun is a type of noun that refers to things that can be perceived through the five senses: sight, hearing, touch, taste, and smell. Examples of concrete nouns include apple, dog, and car. These nouns represent physical objects or entities that we can experience directly in the real world. In contrast to abstract nouns, which represent ideas or concepts that cannot be physically touched, concrete nouns are tangible. For instance, you can see a tree, feel a book, or hear a musical instrument. Understanding concrete nouns helps in identifying and describing the physical aspects of our environment.