Mound Builder

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A member of any of various Native American peoples flourishing from around the 5th century B.C. to the 16th century A.D. especially in the Ohio and Mississippi valleys, practicing settled agriculture and known for their often large burial and effigy mounds.

Century Dictionary and Cyclopedia

1. n. One of a race of people by whom the various earthworks called Indian mounds (see mound) were constructed. That these works are not necessarily of great antiquity, and that they were built by a race in no essential respect different from that found inhabiting the region where they occur when this was first settled by the whites, is the present opinion of nearly all the best-informed investigators of American archæology. See quotation under Indian mounds, above.
2. n. A mound-bird.

WordNet 3.0

1. n. prehistoric Amerindians who built altar mounds
2. n. large-footed short-winged birds of Australasia; build mounds of decaying vegetation to incubate eggs