Amnesia is the Greek word Αμνησία. It is composed by Greek word μνήμη (mnimi means memory) and a- which means the lack of something. So the memory loss is Amnesia.
Amnesia

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“Apathy” derives from the Greek word “ἀπάθεια” (apatheia), which is formed by combining the prefix “ἀ-” (a-) meaning “without” and “πάθος” (pathos) meaning “feeling” or “suffering.”
In Greek, “ἀπάθεια” (apatheia) literally translates to “without feeling” or “without suffering.”