Which term describes the action of making something less bright or strong?

The term that best describes the action of making something less bright or strong is "dim." When you dim something, such as a light, you are specifically reducing its brightness, making it softer or less intense. This word specifically conveys the adjustment of light levels and is often used in contexts related to lighting or visibility, emphasizing the change in luminosity.

While terms like "reduce," "weaken," and "lower" can imply a decrease in intensity or strength, they are more general and do not exclusively relate to light or brightness. For example, to "reduce" could refer to decreasing quantity or degree of anything, while "weaken" pertains to diminishing strength or power, and "lower" might refer to decreasing level or height. In contrast, "dim" captures the specific action of making something less bright, involving a clear visual change.