(1) The external conditions, resources, stimuli etc. with which an organism interacts.
(2) The external surroundings including all of the biotic and abiotic factors that surround and affect the survival and development of an organism or population.
(3) The totality of the surrounding conditions and elements in an individual.
The environments may be regarded as natural environment or built environment.
They may also be marine, atmospheric, or terrestrial according to their attributes.
Word origin: Middle English envirounen, from Old French environner, from environ, round about + -ment.
Related forms: environmental (adjective), environmentally (adverb).
Related terms: environmentalist, environmentalism.
Other: habitat, ecological niche.