Sichuan pepper

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

• noun Any of several spiny East Asian trees or shrubs of the genus Zanthoxylum, especially Z. simulans, having aromatic bark, pinnately compound leaves, and small dry reddish fruit, used as a spice.
• noun The husks of the fruit of any of these plants, used whole or ground.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun countable, uncountable The outer pod of the tiny fruit of a number of species in the genus Zanthoxylum widely grown and consumed in Asia as a spice. Not closely related to black pepper or to chilli peppers.
• noun uncountable Spice made from this pod.
• noun countable A plant producing the pods, Zanthoxylum