pla ‧ cate /pləˈkeɪt $ ˈpleɪkeɪt/ BrE AmE verb [transitive] formal
[ Date: 1600-1700 ; Language: Latin ; Origin: past participle of placare ]
to make someone stop feeling angry SYN appease OPP rile :
These changes did little to placate the unions.
—placatory /pləˈkeɪt ə ri, ˈplækət ə ri $ ˈpleɪkətɔːri/ adjective :
a placatory smile