The term "big operator" is usually used to refer to someone who is highly influential, powerful and successful in their field. There are several synonyms that can be used to describe such an individual. A "mover and shaker" is one term that can be used to describe someone who has a lot of clout in their industry. They are often known for making things happen and getting results. Another synonym for a "big operator" is a "heavy hitter". This term is used to refer to a person who is highly influential and can make significant changes with just a word or two. Lastly, "kingpin" is another synonym for a "big operator" that is often used to describe someone who has a vast network and controls a large portion of the industry they operate in.