Neutral Grain Spirits, sold as "Everclear" in the United states is almost pure alcohol. It is 95% ethanol so drinking it by itself in shots can be harmful over a period of time. It is often used to mix into other beverages, since a few shots will bring an entire pitcher of juice, pop, etc. up to 5% alcohol easily.
The term neutral refers to the substance's neutral odor. The grain from which it is derived can be any of the common cereal grains, though corn may be most common.
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