The phrase "smooth operator" refers to someone who is very skilled, charming, and persuasive in their behavior. They are able to navigate situations effortlessly and with ease, often getting what they want. Full definition
Smooth operators seem so responsible and knowledgeable that it is easy to believe they will be able to take on your responsibilities with no problem. (entrepreneur.com)
After experiencing him and other smooth operators, we have gotten better at identifying them. (entrepreneur.com)
I also had smooth operator which included nutritional yeast which I've never had in a smoothie before but it tasted amazing. (greenthickies.com)