Source : Webster's Revised Unabridged Dictionary (1913)

Chat \Chat\, n.
   1. A twig, cone, or little branch. See {Chit}.

   2. pl. (Mining) Small stones with ore.

   {Chat potatoes}, small potatoes, such as are given to swine.
      [Local.]

Chat \Chat\, v. i. [imp. & p. p. {Chatted}; p. pr. & vb. n.
   {Chatting}.] [From {Chatter}. [root]22.]
   To talk in a light and familiar manner; to converse without
   form or ceremony; to gossip. --Shak.

         To chat a while on their adventures.     --Dryden.

   Syn: To talk; chatter; gossip; converse.

Chat \Chat\, v. t.
   To talk of. [Obs.]

Chat \Chat\, n.
   1. Light, familiar talk; conversation; gossip.

            Snuff, or fan, supply each pause of chat, With
            singing, laughing, ogling, and all that. --Pope.

   2. (Zo["o]l.) A bird of the genus {Icteria}, allied to the
      warblers, in America. The best known species are the
      yellow-breasted chat ({I. viridis}), and the long-tailed
      chat ({I. longicauda}). In Europe the name is given to
      several birds of the family {Saxicolid[ae]}, as the
      {stonechat}, and {whinchat}.

   {Bush chat}. (Zo["o]l.) See under {Bush}.

Source : WordNet®

chat
     n 1: an informal conversation [syn: {confab}, {confabulation}, {schmooze},
           {schmoose}]
     2: birds having a chattering call [syn: {New World chat}]
     3: songbirds having a chattering call [syn: {Old World chat}]
     [also: {chatting}, {chatted}]

chat
     v : talk socially without exchanging too much information; "the
         men were sitting in the cafe and shooting the breeze"
         [syn: {chew the fat}, {shoot the breeze}, {confabulate},
         {confab}, {chitchat}, {chatter}, {chaffer}, {natter}, {gossip},
          {jaw}, {claver}, {visit}]
     [also: {chatting}, {chatted}]

Source : Free On-Line Dictionary of Computing

chat
     
         Any system that allows any
        number of logged-in users to have a typed, real-time, on-line
        conversation, either by all users logging into the same
        computer, or more commonly nowadays, via a {network}.
     
        The medium of {chat} is descended from {talk}, but the terms
        (and the media) have been distinct since at least the early
        1990s.  {talk} is prototypically for a small number of people,
        generally with no provision for {channels}.  In {chat}
        systems, however, there are many {channels} in which any
        number of people can talk; and users may send private
        (one-to-one) messages.
     
        Some well known chat systems to date (1998) include {IRC},
        {ICQ} and {Palace}.
     
        Chat systems have given rise to a distinctive style combining
        the immediacy of talking with all the precision (and
        verbosity) that written language entails.  It is difficult to
        communicate inflection, though conventions have arisen to help
        with this.
     
        The conventions of chat systems include special items of
        jargon, generally abbreviations meant to save typing, which
        are not used orally.  E.g., {re}, {BCNU}, {BBL}, {BTW}, {CUL},
        {FWIW}, {FYA}, {FYI}, {IMHO}, {OTT}, {TNX}, {WRT}, {WTF},
        {WTH}, {}, {}, {BBL}, {HHOK}, {NHOH}, {ROTFL}, {AFK},
        {b4}, {TTFN}, {TTYL}, {OIC}, {re}.
     
        Much of the chat style is identical to (and probably derived
        from) {Morse code} jargon used by ham-radio amateurs since the
        1920s, and there is, not surprisingly, some overlap with {TDD}
        jargon.  Most of the jargan was in use in {talk} systems.
        Many of these expressions are also common in {Usenet} {news}
        and {electronic mail} and some have seeped into popular
        culture, as with {emoticons}.
     
        The {MUD} community uses a mixture of {emoticons}, a few of
        the more natural of the old-style {talk mode} abbreviations,
        and some of the "social" list above; specifically, MUD
        respondents report use of {BBL}, {BRB}, {LOL}, {b4}, {BTW},
        {WTF}, {TTFN}, and {WTH}.  The use of "{re}" or "rehi" is also
        common; in fact, MUDders are fond of "re-" compounds and will
        frequently "rehug" or "rebonk" (see {bonk/oif}) people.  In
        general, though, MUDders express a preference for typing
        things out in full rather than using abbreviations; this may
        be due to the relative youth of the MUD cultures, which tend
        to include many touch typists.  Abbreviations specific to MUDs
        include: {FOAD}, ppl (people), THX (thanks), UOK? (are you
        OK?).
     
        Some {BIFF}isms (notably the variant spelling "d00d") and
        aspects of {ASCIIbonics} appear to be passing into wider use
        among some subgroups of MUDders and are already pandemic on
        {chat} systems in general.
     
        See also {hakspek}.
     
        {Suck article "Screaming in a Vacuum"
        (http://www.suck.com/daily/96/10/23/)}.
     
        (1998-01-25)