Indispensables, also known as essentials or must-haves, refer to things that are necessary and cannot be done without. Synonyms for indispensables include vital, crucial, fundamental, necessary, important, and imperative. When we use the term indispensables, we are talking about those items that we rely on every day to get things done, such as food, water, shelter, clothing, and medicine. In a professional setting, indispensables may refer to skills or tools that are necessary to successfully complete a job or project. The word indispensables emphasizes the importance of these items and emphasizes that they cannot be replaced or substituted.