The term 'become popular on social media' can be summarized by the crossword solution 'TREND, ' which is a five-letter word. Trending is a phenomenon that occurs when a topic or idea becomes popular on social media platforms such as Twitter, Instagram, and Facebook. It is often used to describe the most talked about topics or ideas at any given time. When something trends, it means that it has become popular enough to be noticed by a large number of people.