Definition from Wiktionary, the free dictionary placard (plural
placards) - A sheet of paper or cardboard with a written or
printed announcement on one side for display in a public place.
a sheet of paper or cardboard - To affix a placard to. - To
announce with placards. - to placard a sale placard m (plural
placards) - A cupboard, cabinet or closet built against or into
a wall. - An ad that is felt to be injurious, seditious or in
otherwise bad taste. - (dated) A placard. Usage notes  - The use
of placards for announcements by authorities having mostly
disappeared, the word affiche frequently replaces it in that
meaning.