What does wild rice mean in cooking?

wild rice means: North American grass that is often cooked as rice, and sometimes served with meat. (in Cooking Dictionary)

What else does wild rice mean?

• A grain from Zizania aquatica, a aquatic plant that looks like rice. It is grown in Canada and the United States. They are black with an earthy and nutty taste. (in Cooking Dictionary)
• One of many aquatic grasses in the genus Zizania Particularly North America and Asia Z. palustris North-central North America is where the edible grain is grown. (in Merlin Dictionary)
• Any of these plants can produce grain. (in Merlin Dictionary)