The phrasal verb "chat up" is predominantly used in informal speech, especially common in British English. It is most often used to describe the act of engaging someone in conversation with the intent to flirt or show romantic interest. This expression is typical in social settings such as bars, parties, or other gatherings where casual, playful interactions are likely. Although "chat up" can be understood by speakers of English in various regions, its use may be less frequent in American English, where alternatives like "hit on" might be used instead. In formal contexts, this phrasal verb is rarely appropriate due to its casual and often personal nature. The phrase can also imply a degree of charm or persuasion, hinting at an effort to win someone over or to make a positive impression.
B1
PreIntermediate
1. To engage someone in conversation in a flirtatious or friendly manner, often with romantic intentions.
He tried to chat up the girl at the bar, but she wasn't interested.
At the party, Tim spent the entire evening chatting up his new coworker.
She said she prefers when people chat her up in a humorous way.