Not impressible; not sensitive; apathetic.(adjective)
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Use "unimpressible" in a sentence
"Sweden; Leibnitz; the august house of Brunswick; Tillotson; the emperor of China; the Parliament of England; the Council of the great Mogul; in short, all you who do not believe one word which I have taught in my courses on divinity, I declare to you, that I regard you all as pagans and publicans, as, in order to engrave it on your unimpressible brains, I have often told you before."
"For what good, say these unimpressible and incredulous men, for what good was this miracle?"
"No, he needed to do something dramatic-something that would impress a woman as sleek and cool and, well, unimpressible as Tammy Hudson surely was."