black cumin

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

• noun The small black pungent seeds of an annual herb (Nigella sativa) of the buttercup family native to southwest Asia, used as a seasoning in southern and western Asian cuisines and for medicinal purposes.
• noun The dark brown, crescent-shaped seeds of an herb (Bunium persicum) of the parsley family native to southwest Asia, used as a seasoning in southern and western Asian cuisines.