Is there a single word for "one who speaks/boasts a lot about everything"?

I think you may want pretentious.

Not a single word, but my favourite expression for this sort of person is all hat and no cattle.


Some choices:

  • know-it-all

    A person who behaves as if they know everything

  • braggart

    A person who boasts about their achievements or possessions

  • blow-hard

    A boastful or pompous person

(Definitions from Oxford Dictionaries Online)


Poseur comes to mind, particularly if that person doesn't live up to the qualities he or she boasts about.