(ˈ)im|plakəbəl, əmˈp- also -plāk- adjective
Etymology: Middle French or Latin; Middle French, from Latin implacabilis, from in- in- (I) + placabilis placable — more at placable
1.
a. : not placable : not capable of being appeased or pacified : inexorable
an implacable enemy
an implacable resentment
single-minded and implacable , even unmerciful, in his servitude to the law — M.S.Mayer
b. : incapable of being significantly changed or modified : following a due unalterable course
the implacable lives of plants — Clifford Gessler
the implacable logic of his career
the measured, arranged, implacable movement of the universe — A.J.Cronin
2. : incapable of being relieved or mitigated
an implacable disease
the horns of an implacable dilemma — J.C.Powys
his implacable interest in love — William McFee
watched that implacable blaze of space as far as the mountainous horizon — D.C.Peattie
• im·placa·ble·ness -bəlnə̇s noun
• im·placa·bly -blē, -bli adverb