You are correct!
From our dictionary:
Pronunciation: (plA'kAt, plak'At), [key]
âv.t., -catâ¢ed, -catâ¢ing.
to appease or pacify, esp. by concessions or conciliatory gestures: to placate an outraged citizenry.
Pronunciation: (plak'At, -it), [key]
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.