A tattoo is a form of body modification in which a design is made by inserting ink, dyes, and pigments, either indelible or temporary, into the dermis layer of the skin to change the pigment. The art of making tattoos is tattooing. The word tattoo, or tattow in the 18th century, is a loanword from the Samoan word tatau, meaning "to mark something." The Oxford English Dictionary gives the etymology of tattoo as "In 18th c. tattaow, tattow. From Polynesian (Samoan, Tahitian, Tongan, etc.) tatau. In Marquesan, tatu.