artefact

noun

• An object made or shaped by human hand or labor.
• An object made or shaped by some agent or intelligence, not necessarily of direct human origin.
• Something viewed as a product of human agency or conception rather than an inherent element.
• 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.

  "The spot on his lung turned out to be an artifact of the X-ray process."

• An object, such as a tool, ornament, or weapon of archaeological or historical interest, especially such an object found at an archaeological excavation.

  "The dig produced many Roman artifacts."

• 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.
• A perceptible distortion that appears in an audio or video file or a digital image as a result of applying a lossy compression algorithm.

  "This JPEG image has been so highly compressed that it has unsightly compression artifacts, making it unsuitable for the cover of our magazine."