What does "placard" mean?

Placard: Permission given by authority; a license; as, to give a placard to do something. [Obs.] ller.

Additional senses

  1. 2.A written or printed paper, as an advertisement or a declaration, posted, or to be posted, in a public place; a poster.
  2. 3.(Anc. Armor) An extra plate on the lower part of the breastplate or backplate. Planché.
  3. 4.Etym: [Cf. Placket.] A kind of stomacher, often adorned with jewels, worn in the fifteenth century and later.
  4. 5.To post placards upon or within; as, to placard a wall, to placard the city.
  5. 6.To announce by placards; as, to placard a sale.

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