To talk in a light and familiar manner; to converse without form or ceremony; to gossip.
- To converse in an easy, familiar manner; talk lightly and casually.
- Computer Science To participate in a synchronous exchange of remarks with one or more people over a computer network.
- An informal, light conversation.
- Computer Science A synchronous exchange of remarks over a computer network.
- Any of several birds known for their chattering call, as of the genera Saxicola or Icteria.
- chat up To engage (someone) in light, casual talk: "He would be . . . chatting up folks from Kansas” ( Vanity Fair).