Talk Up Meaning

(intransitive) To speak in a plain and candid way.

Example: 1851, Herman Melville, Moby Dick, chapter 19
  â€œLook here, friend,” said I, “if you have anything important to tell us, out with it; but if you are only trying to bamboozle us, you are mistaken in your game; that’s all I have to say.”
  And it’s said very well, and I like to hear a chap talk up that way; you are just the man for him—the likes of ye.