A sandwich board.

plural of A board

A group of people elected by stockholders to establish corporate policies and make management decisions.

Honestly; openly.

In open sight; without trick, concealment, or deception.

(Incoterm) without charge to the purchaser for delivery on board a carrier (originally a ship), at a specified location or point; used in such phrases as FOB destination to specify the point where the title of goods passes from the seller to the buyer

(nautical) The group of sailors who were selected to board an enemy ship and, when in control, to make such repairs to rigging and sail that the ship could be taken to port as a prize

(computing, Macintosh) A motherboard.

A person-sized, wearable billboard or advertisement consisting of two printed boards strung together so that they hang over the shoulders, or simply set out on a street.

To advertise or campaign using a sandwich board; to wear a sandwich board.