artifact

noun:

1. A perceptible distortion that appears in an audio or video file or a digital image as a result of applying a lossy compression algorithm.
2. A finding or structure 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.
3. An object, such as a tool, ornament, or weapon of archaeological or historical interest, especially such an object found at an archaeological excavation.
4. An object made or shaped by human hand or labor.
5. Something viewed as a product of human agency or conception rather than an inherent element.
6. An object made or shaped by some agent or intelligence, not necessarily of direct human origin.
7. An appearance or structure in protoplasm due to death, the method of preparation of specimens, or the use of reagents, and not present during life.