The term "unadulterated" refers to something that is pure and untarnished. Therefore, the antonyms for this word would be those that denote impurity or contamination. Some possible antonyms include "adulterated," "contaminated," "tainted," "corrupted," "spoiled," or "impure." These words indicate that something has been mixed or altered in a negative way, losing its original purity or quality. For instance, an adulterated food item might contain harmful substances or ingredients, while a corrupted data file might have errors or viruses. By understanding the antonyms of "unadulterated," we can better appreciate the value of purity and genuine authenticity.