A clean environment refers to a place or space that is free from pollution, contamination and other forms of dirtiness. This could mean having clean air, water, soil, and vegetation without any form of waste materials or harmful substances. A clean environment also implies proper sanitation and hygiene practices such as the absence of litter, garbage, and stray animals. The term "clean" is often used to describe a place that is visually appealing, well-organized, and free from clutter. In summary, a clean environment refers to a healthy and safe space for humans, plants, and animals to thrive in.