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I__________
Definitions
incapable of being overcome, challenged or refuted
Used in a sentence
“Jurgis got up, wild with rage; but the door was shut and the great castle was dark and impregnable.”
“The reproductive strategies of troop members, especially those of impregnable females, are suggested to influence patterns of range use.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer0 curated clues
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