Final answer:
A term that denotes a collection of interacting, interrelated, or interdependent elements forming a complex whole is a 'system.' It can be applied in sociology as a group, in biology as an ecosystem, and in physics or engineering as interconnected components.
Step-by-step explanation:
The definition of a term that describes a collection of interacting, interrelated, or interdependent things or parts forming a complex or unified whole, especially to serve a common purpose, is a system. This concept is broadly applicable across various disciplines, including sociology, biology, and technology. In sociology, a group can be understood as a system if it consists of people who interact with some frequency and share a sense of aligned identity. In biology, ecosystems represent a type of system where living organisms and their physical environment are interconnected. Similarly, in physics and engineering, systems are collections of elements or components that interact according to conservation laws.