According to the etymology, or word origin website, etymonline it comes:
from a Polynesian noun (such as Tahitian and Samoan tatau, Marquesan tatu) "puncture, mark made on skin."
And from 17th century European pidgin to 21st century American English, the tattoo process has evolved, too. But the images people choose, where once reflective of tribal heritage and culture, might have arguably devolved.
Case in point this gallery. Click on through to see the worst tattoos we could find on the Internet.