Definition of lighten up

The phrase "lighten up" refers to relaxing, letting go of stress or tension, and adopting a more carefree and optimistic attitude. Its origin can be traced back to the early 20th century in English-speaking communities, particularly in the United States. The word "lighten" in this context comes from the verb "to lighten," which has two principal meanings: to become less heavy or dense, and to become less severe or serious. In the former meaning, "lighten up" is used to indicate a reduction in physical weight or load, while in the latter meaning, the phrase suggests an easing or decrease of mental or emotional burden. The term's usage as a command or suggestion to "lighten up" gained prominence during the late 1960s and early 1970s, particularly among the counterculture and hippie movements, as a way of encouraging lifestyle changes reflecting a more positive and casual approach to life. In popular culture, the phrase has been used in a variety of contexts, including comedies, musicals, and sports, as a way of imparting a sense of humor, optimism, and lightheartedness. Its popularity continues to this day, with the term being commonly used in various settings, from social gatherings to professional relationships, as a way of promoting a more relaxed and stress-free experience.