Final answer:
The term 'complicated' describes something with many interconnected parts that are arranged in a sophisticated or complex way, making the subject difficult to understand or deal with.
Step-by-step explanation:
The term 'complicated' refers to something that has multiple parts, aspects, or elements that are interconnected in a sophisticated, intricate, or elaborate way. This typically makes the subject difficult to understand, solve or deal with.
When a system or a problem is complicated, it means option 3) Having many parts arranged in a complicated way.
A good example to understand 'complicated' can be derived from the chaos theory, which is a predecessor to complexity. Systems described as chaotic are highly sensitive to initial conditions, making their long-term behavior unpredictable and complex in nature.