impregnable
im-PREG-nuh-bul
/ɪmˈpreɡnəbl/
Unable to be captured or broken into by force; impossible to overcome or refute.
Connotes complete invulnerability to assault, whether describing stone walls or an airtight logical argument.
The story behind the word. Altered from Middle English 'imprenable', adapted from Old French 'imprenable' (from 'in-' not + 'prendre' to take, from Latin 'prehendere' to seize). The 'g' was added in English in the 16th century under false analogy with words ending in '-gn'.
Word relationships
- invulnerable: Invulnerable means incapable of being wounded, while impregnable means unable to be taken by force or conquered.
- unassailable: Unassailable means unable to be attacked or questioned.
- vulnerable: Open to physical or emotional attack.
- defenseless: Lacking any protection.
Commonly confused with
- impermeable: Impermeable means fluid cannot pass through; impregnable means an enemy cannot capture or breach it.
Word family
- impregnability (noun): The quality of being impossible to capture or overcome.
- impregnably (adverb): In an impregnable manner.
Collocations
- impregnable fortress
- impregnable defense
- impregnable logic
Example sentences
- "Perched high on vertical cliffs, the fortress was considered virtually impregnable to direct infantry attack." Military fortress description
- "The defense attorney presented an impregnable alibi that established her client was out of the country." Legal argument
Memory hook
IM-PREG-NABLE = IM (not) + PREGNABLE (grab-able) -> Cannot be seized! Cannot be captured or seized.
When not to use
Do not confuse with 'pregnant' or related terms; the 'preg' root here comes from Latin prehendere (to seize).
Fun facts
- The fortress of Gibraltar was long considered impregnable until modern air warfare altered defensive military strategy.
Explore more words
incorruptible, immutable, imperishable, dauntless, imperturbable, buttress
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