Also found in: Thesaurus, Medical, Legal.

im·preg·na·ble 1

1. Impossible to capture or enter by force: an impregnable fortress.
2. Difficult or impossible to attack, challenge, or refute with success: an impregnable argument.

[Middle English imprenable, from Old French : in-, not (from Latin in-; see in-1) + prenable, pregnauble, pregnable; see pregnable.]

im·preg′na·bly adv.

im·preg·na·ble 2

Capable of being impregnated.

ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.impregnably - in an impregnable manner; "the sight of that bland, impregnably righteous face has been enough to make their blood run cold"
References in classic literature ?
Finally, though, as will soon be revealed, its contents partly comprise the most delicate oil; yet, you are now to be apprised of the nature of the substance which so impregnably invests all that apparent effeminacy.
At their zenith they appear impregnably all-powerful.
Try out the impregnably tall Great Wall of Chocolate (Dh55) or the decadent Banana Spring Rolls (Dh35) before you mass message your friends to try out this must-visit Abu Dhabi bistro.