Which term relates to uncertainty about something negative occurring in the future?

The term that relates to uncertainty about something negative occurring in the future is apprehension. This word specifically captures the feeling of anxiety or fear regarding potential future events that may have unfavorable outcomes. When someone feels apprehensive, they are often aware of possible dangers or challenges that could arise, leading to a heightened sense of concern or unease.

In contrast, assurance conveys a sense of security or certainty about a situation, which does not align with the idea of uncertainty. Confidence suggests a strong belief in oneself or in a positive outcome, while excitement denotes a state of eager anticipation that is generally associated with positive experiences, rather than fear of negative ones. Thus, apprehension is the most appropriate term in this context, as it embodies the specific nature of feeling uncertain and worried about adverse future events.