au fait /ofɛt, fɛ/
  Au fait  Expert; skillful; well instructed.
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  au fait
       adj : being up to particular standard or level especially in being
             up to date in knowledge; "kept abreast of the latest
             developments"; "constant revision keeps the book au
             courant"; "always au fait on the latest events"; "up on
             the news" [syn: abreast of(p), au courant, up
             on(p)]