"Monkey Business" refers to playful or mischievous behavior, often associated with the antics of monkeys. These animals are known for their curious nature and tendency to engage in playful activities, which can sometimes lead to trouble. The term is commonly used to describe situations where someone is being silly or causing minor chaos. In a broader context, "monkey business" can also refer to any kind of trickery or deceitful behavior. It is often used in a lighthearted manner to describe harmless pranks or fun activities that may disrupt the norm but are not meant to cause serious harm.