Chat, informally can be described in two ways: CONFAB (6 letters) and RAP (3 letters). CONFAB is a verb meaning to converse or talk informally. It is derived from the Latin word 'confabulari' which means to talk together. RAP is a noun meaning an informal conversation or discussion. It is derived from the Middle English word 'rappen' which means to talk quickly. Both words are used to describe informal conversations or discussions.