saw palmetto

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A small creeping palm (Serenoa repens) of the southeast United States, having palmately divided leaves, petioles with sharp spines, and black fruit borne on panicles.
• noun A dried preparation of the fruit of this plant used as a nonprescription herbal remedy that is supposedly beneficial for disorders of the prostate gland.

from The Century Dictionary.

• noun See Serenoa.

from the GNU version of the Collaborative International Dictionary of English.

• See under palmetto.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun small hardy clump-forming spiny palm of southern United States