Abstract nouns are words that represent ideas, qualities, or conditions that cannot be perceived through the five senses. Unlike concrete nouns, which refer to physical objects like apple or car, abstract nouns describe concepts such as happiness, freedom, or justice. They often express emotions, states of being, or characteristics. These nouns are essential in language as they help convey complex thoughts and feelings. For example, when someone talks about love or courage, they are using abstract nouns to express intangible experiences. Understanding abstract nouns enhances communication by allowing us to discuss ideas that go beyond the physical world.