Incapable of being seized by attack
One Word SubstitutionsHARD
Impregnable
Incapable of being seized by attack
One Word SubstitutionsHARD
Impregnable
Learning Progress
Examples
"The fortress was considered impregnable for centuries."
"Good encryption makes data impregnable to casual attacks."
Source: One Word SubstitutionsAdded: 11/13/2025
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Words Being Learned104
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