Definition of “chat” - Learner’s Dictionary

chat

verb [ I ] us uk /tʃæt/ present participle chatting, past tense and past participle chatted
Who was that you were chatting to at the bar?We were just walking along, chatting.I could chat with him for hours.They were chatting away like old friends.Come on children, stop chatting and settle down please!
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

See also

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