What does placate mean?

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From our dictionary:

pla•cate

Pronunciation: (plA'kAt, plak'At), [key]
v.t., -cat•ed, -cat•ing.
to appease or pacify, esp. by concessions or conciliatory gestures: to placate an outraged citizenry.

plac•ate

Pronunciation: (plak'At, -it), [key]
n. Armor.
a piece of plate armor of the 15th to the 18th century protecting the lower part of the torso in front: used esp. as a reinforcement over a breastplate. Also,placard,plac'cate,plackart.