In archaeology, scrapers are unifacial tools that were used either for hideworking or woodworking purposes. Whereas this term is often used for any unifacially flaked stone tool that defies classification, most lithic analysts maintain that the only true scrapers are defined on the base of use-wear, and usually are those that were worked on the distal ends of blades-- i.e., "end scrapers" or grattoirs. Other scrapers include the so-called "side scrapers" or racloirs, which are made on the longest side of a flake, and notched scrapers, which have a cleft on either side that may have been used to attach them to something else.
Most scrapers are either circle or blade-like in shape. The working edges of scrapers tend to be convex, and many have trimmed and dulled lateral edges to facilitate hafting. One important variety of scraper is the thumbnail scraper, a scraper shaped much like its namesake. This scraper type is common at Paleo-Indian sites in North America.