In the business and technology sectors, a 'unicorn' refers to a privately held startup company that has reached a valuation of over $1 billion. The term highlights the rarity and exceptional success of such companies, which are often seen as leaders in innovation and rapid growth within their industries. Unicorns are typically associated with disruptive technology, strong investor interest, and the potential to significantly impact markets. The term was popularized in the early 2010s to emphasize how unusual it was for startups to achieve such high valuations.