Sustainments, which refers to the means of sustaining or maintaining something, can have a number of antonyms depending on the context. For example, antonyms for financial sustainments might include bankruptcies, debts, or losses. Other potential antonyms could include abandonment, neglect, or deterioration, referring to the opposite of sustaining or maintaining something in good condition. In the context of food or nutrition, antonyms to sustainments might include hunger or starvation. Ultimately, the antonyms for sustainments may vary depending on the particular meaning and usage of the word in question.