Capable of being asked or persuaded; willing or able to respond to requests or appeals.
From 'entreat' (from Old French 'entraiter': en- + traiter meaning to treat or negotiate) + the suffix -able (capable of). Something entreatable can be influenced by entreaties.
What makes someone 'entreatable' is a kind of openness—you can entreat them, meaning they're not hardened against appeals to their sense of justice, compassion, or reason, which is why it's actually a quality we want in leaders and judges.
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