The definition goes way back to early Tool and Dye Makers. After inspecting a finished manufactured or repaired part, the Toolmaker/machinist would
tighten all parts and screws (Screwed), Use Blueing a blue paint lke stain that stuck easaly to metal (blued) and, then put his inspectors mark through the blue paint with a sharp scriber (tattooed) The part has passed inspection, it's been screwed, blued and tattooed and ready for release from the machine shop.
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