What feeling is described by "lassitude"?

The term "lassitude" specifically refers to a state of physical or mental weariness, indicating a lack of energy or vitality. It encompasses feelings of lethargy and fatigue, often resulting from exhaustion or illness. This makes it aligned with the notion of diminished energy, which perfectly captures the essence of lassitude. Understanding this term can help identify its usage in various contexts, particularly in literature or descriptions that emphasize fatigue or a feeling of being drained.

The other choices represent feelings that are contrary to lassitude. A state of mental clarity suggests alertness and focus, while enhanced energy and vigor imply a high level of enthusiasm and activity. Indecisiveness and uncertainty relate to cognitive struggle but do not convey the physical or mental fatigue associated with lassitude. Thus, the choice reflecting weariness and diminished energy is the most accurate interpretation of the term.