Definition of organism
- the nation is not merely the sum of individual citizens at any given time, but it is a living organism, a mystical body … of which the individual is an ephemeral part
- —Joseph Rossi
- a multicellular organism
A human being is a complex organism.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'organism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: an individual living thing
: a system with many parts that depend on each other and work together
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