Meaning of “chat” - Learner’s Dictionary

chat

verb [ I ] uk us /tʃæt/ (present participle chatting, past tense and past participle chatted)
TALK

A2 to talk with someone in a friendly and informal way:

I wanted to chat to you about the party on Saturday.
COMPUTING

to have a conversation with other people on the Internet, when you write down what you want to say, and can see immediately what other people are writing

(Definition of “chat verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)