artifact

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

• noun An object produced or shaped by human craft, especially a tool, weapon, or ornament of archaeological or historical interest.
• noun Something viewed as a product of human conception or agency rather than an inherent element.
• noun A phenomenon or feature not originally present or expected and caused by an interfering external agent, action, or process, as an unwanted feature in a microscopic specimen after fixation, in a digitally reproduced image, or in a digital audio recording.
• noun An inaccurate observation, effect, or result, especially one resulting from the technology used in scientific investigation or from experimental error.

from The Century Dictionary.

• noun Anything made by art; an artificial product.
• noun A natural object modified by human art.
• noun Also artefactum.
• Not natural, but produced by manipulation, as some microscopic feature in a hardened tissue.
• Also spelled artefact.

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

• noun (Archæol.) A product of human workmanship; -- applied esp. to the simpler products of aboriginal art as distinguished from natural objects.
• noun Any product of human workmanship; -- applied both to objects made for practical purposes as well as works of art. It is contrasted to natural object, i.e. anything produced by natural forces without the intervention of man.
• noun (Biol.) A structure or appearance in protoplasm due to death, method of preparation of specimens, or the use of reagents, and not present during life.
• noun (Technology) an object, oservation, phenomenon, or result arising from hidden or unexpected causes extraneous to the subject of a study, and therefore spurious and having potential to lead one to an erroneous conclusion, or to invalidate the study. In experimental science, artifacts may arise due to inadvertant contamination of equipment, faulty experimental design or faulty analysis, or unexpected effects of agencies not known to affect the system under study.

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

• noun An object made or shaped by human hand.
• noun archaeology An object, such as a tool, weapon or ornament, of archaeological or historical interest, especially such an object found at an archaeological excavation.
• noun Something viewed as a product of human conception or agency rather than an inherent element.
• noun A structure or finding in an experiment or investigation that is not a true feature of the object under observation, but is a result of external action, the test arrangement, or an experimental error.
• noun An object made or shaped by some agent or intelligence, not necessarily of direct human origin.

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

• noun a man-made object taken as a whole