im·placa·bil·i·ty \(ˌ)imˌplakəˈbīləd.ē, əm-, -lətē, -i also -plāk-\noun Etymology: Late Latin implacabilitas, from Latin implacabilis + -itas -ity : the quality or state of being implacable < the implacability of his resentments — Jane Austen > < the implacability of a Greek tragedy — Arthur Schlesinger b. 1917 >