informal conversation or talk conducted in an easy familiar manner

the exchange of messages in an internet or other network chatroom

any Old World songbird of the subfamily Turdinae (thrushes, etc) having a harsh chattering cry

any of various North American warblers, such as Icteria virens (yellow-breasted chat)

any of various Australian wrens (family Muscicapidae) of the genus Ephthianura and other genera

to talk in an easy familiar way

to exchange messages in a chatroom