Billboard

n. large sign board for advertisements or notices

n. weekly American magazine devoted to music and the recording industry (includes the weekly charts for top songs and albums)

A billboard is a large outdoor advertising structure (a billing board), typically found in high traffic areas such as alongside busy roads. Billboards present large advertisements to passing pedestrians and drivers. Typically showing large, witty slogans and distinctive visuals, billboards are highly visible in the top designated market areas.
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Noun
1. large outdoor signboard
(synonym) hoarding
(hypernym) signboard, sign

(n.)
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.
  

(n.)
A flat surface, as of a panel or of a fence, on which bills are posted; a bulletin board.
  

outdoor poster site; measured in sheet sizes e.g. 4, 16, 32, 48, 96 sheet (see RMD communications/outdoor link).

special treatment, such as moving units, flashing lights, etc., used to gain added attention; more commonly used on rotation, permanent, or spectacular units.

annual traffic volume passing the site for the year, divided by 365.

outdoor circulation is based on traffic volume and is made up of automotive, pedestrian, and mass transportation.

potential viewers the number of people passing an advertising structure who have an opportunity to view it.

the direction the poster faces may be seen to traffic flow; e.g. a south facing panel can be read by north-bound traffic.

the number of times an average family or individual has the opportunity to be exposed to an advertising message during a defined period of time. In outdoor, frequency and reach usually refer to the calendar month as the basic reference, since this time period coincides with standard contract and exposure practices.

total number of impressions delivered by a media schedule, expressed as a percentage of the population. For outdoor, GRPs generally refer to daily circulation generated by the entire showing.

advertising structures with electrical equipment installed for illuminating the advertising message at night.

a mobile poster panel that is wheeled to a given location.

the number of pieces of paper needed to cover a poster panel area.

outdoor poster size, 40in x 90in (1016mm x 2304 mm).

outdoor poster size, 10ft x 6ft 8ins (3048mm x 2032 mm).

outdoor poster size; 30ft x 10ft (3048mm x 8128mm).