The term "world ecosystem" encompasses the entire ecological system of the planet. However, there are several synonyms that can be used in place of this term to refer to specific aspects of the planet's environment. These synonyms include global ecology, planetary ecology, biosphere, natural world, and environment. Global ecology refers to the scientific study of the interactions between living organisms and their physical environment on a global scale. Planetary ecology, on the other hand, refers to the study of ecosystems beyond Earth, including those on other planets. Biosphere and natural world both refer to the living and non-living components of the earth's ecosystem, while environment encompasses all external physical, chemical, and biological factors affecting living organisms.