Environment refers to the surroundings around us. It includes both natural and built environments. It also refers to the circumstances or conditions that surrounds one object also known as our surroundings. Surrounding conditions, influences, or forces, by which living forms are influenced and modified in their growth and development is also known as the environment. For example, in Singapore, everything around us is the environment, the buildings is the built environment, the trees is the natural environment and then the humans (us) is the organisms being affected.
Sources from: BrainyQuote, Wikipedia and the Free Dictionary.