Definition of fallout

The word "fallout" has its origins in the early 20th century, primarily in the context of nuclear explosions. During the first nuclear test in 1945, physicist J. Robert Oppenheimer used the term "fallout" to describe the radioactive particles that spread outward from the test site, contaminating the surrounding area. The term was coined from the phrase "falling out," meaning to scatter or disperse. Initially, fallout referred to the radioactive dust, dirt, and debris that fell to the ground after an atomic blast. Over time, the term expanded to encompass the radioactive particles suspended in the air, which could also "fall out" and contaminate the environment. Today, "fallout" is used metaphorically to describe the unintended consequences or aftermath of a situation, such as a divorce or a financial crisis.