What is the origin of the idiom "smack one's lips" and when to use it?

The phrase "smack one's lips" has its origins in the physical action of smacking or pressing one's lips together. The exact origin of the phrase is difficult to pinpoint, as it has likely been used in various forms across different cultures and languages throughout history. The action of smacking one's lips is instinctive and natural when savoring or enjoying something tasty. Over time, the phrase "smack one's lips" came to be used figuratively to convey a sense of anticipation, satisfaction, or relishing something in a non-literal sense. It is a common expression used to describe the enjoyment or anticipation of something pleasurable.