'Billboard' definitions:

Definition of 'billboard'

From: WordNet
noun
Large outdoor signboard [syn: billboard, hoarding]

Definition of 'Billboard'

From: GCIDE
  • Billboard \Bill"board`\, n.
  • 1. (Naut.) 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. --Totten. [1913 Webster]
  • 2. A flat surface, as of a panel or of a fence, on which bills are posted; a bulletin board. especially, A large board out of doors and visible to passers-by, on which the space is rented for advertising purposes; also, the advertising displayed on such a board. [1913 Webster +PJC]