What term is used for assistance or support that is supplementary?

The term that signifies assistance or support that is supplementary is "auxiliary." This word refers to something that provides additional help or support, often meant to enhance or complement primary resources or services. In various contexts, such as healthcare, education, and even machinery, auxiliary components or personnel play a vital role in sustaining or improving the functionality and effectiveness of the main system or process. For example, in a medical setting, auxiliary staff like nurse assistants help physicians by taking on supportive tasks that allow for better patient care.

The other terms listed do not align with the meaning of supplementary assistance. "Astringent" refers to a substance that tightens tissues or constricts bodily functions, often used in a medical or cosmetic context. "Astute" denotes someone who is very perceptive or has sharp insight, often in decision-making, but does not imply support or assistance. "Audacious" describes a bold or daring approach, particularly in actions or ideas, rather than referring to supplementary help.