The quality or condition of being vulnerable to attack or criticism; the degree to which something can be assailed.
From 'assail' + '-ability' (quality of being; from Latin 'habilis'). This noun formation follows the productive English pattern of adding '-ability' to verbs to create abstract nouns describing capacity or quality.
While 'assail' is a common verb, 'assailability' is rarely used, yet it perfectly captures the concept of vulnerability—it's the philosophical quality that makes something open to attack, whether physically, logically, or rhetorically.
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