/ˈbīˌōm/
Noun, pl. biomes
1. A large naturally occurring community of flora and fauna occupying a major habitat. (Google Dictionary)
2. Climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms,[1] and are often referred to as ecosystems. (wikipedia.org)
3. Any major regional biological community such as that of forest or desert. (wiktionary.org)
4. A major ecological community of organisms adapted to a particular climatic or environmental condition on a large geographic area in which they occur. (biology-online.org)
Word origin: bi: variant of bio-, esp. before a vowel + -ome: New Latin -ōma, -ōmat.