billboard

/B IH1 L B AO0 R D/
noun
  1. 1

    A very large outdoor sign, generally used for advertising.

  2. 2

    A flat surface, such as a panel or fence, on which bills are posted; a bulletin board.

  3. 3

    A piece of thick plank, armed with iron plates, and fixed on the bow or fore-channels of a vessel, for the bill or fluke of the anchor to rest on.

  4. 4

    A sprite that always faces the screen, no matter which direction it is looked at from.

Source: https://en.wiktionary.org/wiki/billboard