Which term refers to a substance that changes color in the presence of an acid or a base?

The term "Indicator" specifically refers to a substance that undergoes a noticeable change, such as a color shift, in response to acidity or basicity in its environment. These substances are vital in chemistry and various scientific fields, as they offer a visual representation of pH levels and help in identifying whether a solution is acidic, neutral, or basic.

Indicators can be natural, like litmus derived from certain lichens, or synthetic, such as phenolphthalein or bromothymol blue, and each has a specific range of pH in which it changes color. This property is essential in laboratory settings and practical applications, such as testing the pH of soil, water, or solutions for various purposes.

The other terms do not relate to this concept; "Incident" generally refers to an event or occurrence, "Individual" pertains to a single person or entity, and "Inebriation" refers to the state of intoxication typically due to alcohol consumption. Thus, they do not encompass the definition or functionality of a substance that changes color in the presence of acids or bases.