individual

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Of or relating to an individual, especially a single human.
• adjective By or for one person.
• adjective Existing as a distinct entity; separate.
• adjective Marked by or expressing individuality; distinctive or individualistic.
• adjective Special; particular.
• adjective Serving to identify or set apart.
• noun A single human considered apart from a society or community.
• noun A human regarded as a distinctive or unique personality.
• noun A single organism as distinguished from a species, community, or group.
• noun A member of a collection or set; a specimen.

from The Century Dictionary.

• Indivisible; inseparable.
• Not susceptible of logical subdivision; determinate in every respect; having a continuity of existence in all its changes; not divisible without loss of identity.
• Of but one person or thing; pertaining or peculiar to, or characteristic of, a single person or thing, or each separate person or thing: opposed to collective: as, individual character; individual labor or effort; individual action.
• Serving or intended for the use of one person only: as, an individual salt-cellar.
• Of which each is different or of a different design from the others: as, a set of individual coffee-cups (that is, a harlequin set).
• noun A single thing; a being, animate or inanimate, that is or is regarded as a unit.
• noun That which is not susceptible of logical subdivision, but is completely determinate, so that only one of a pair of contradictory attributes can be possessed by it.
• noun A thing which by being in only one place at one time, or otherwise, has a continuity of existence in time.
• noun Especially, a human being; a person.
• noun In biology, any organism or part of an organized whole regarded as having (actually or in certain relations) an independent existence. The word is often applied specifically to one of a group or colony of organisms to distinguish it from the colony or group. Thus, many botanists regard each bud as a true individual, the whole plant or tree constituting a colony or compound organism.
• noun A person merely; a man.
• noun In biology: A living being considered as unique or different from its kind and from the rest of nature, without reference to its morphological or physiological independence or dependence. It is in this sense that an organism is termed an individual with reference to reproduction and inheritance.

from the GNU version of the Collaborative International Dictionary of English.

• noun A single person, animal, or thing of any kind; a thing or being incapable of separation or division, without losing its identity; especially, a human being; a person.
• noun An independent, or partially independent, zooid of a compound animal.
• noun The product of a single egg, whether it remains a single animal or becomes compound by budding or fission.
• adjective Not divided, or not to be divided; existing as one entity, or distinct being or object; single; one.
• adjective Of or pertaining to one only; peculiar to, or characteristic of, a single person or thing; distinctive

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A person considered alone, rather than as belonging to a group of people.
• noun A single physical human being as a legal subject, as opposed to a legal person such as a corporation.
• noun An object, be it a thing or an agent, as contrasted to a class.
• adjective Relating to a single person or thing as opposed to more than one.
• adjective Intended for a single person as opposed to more than one person.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a human being
• adjective concerning one person exclusively
• adjective characteristic of or meant for a single person or thing
• adjective being or characteristic of a single thing or person
• adjective separate and distinct from others of the same kind
• noun a single organism