not admitting of penetration or passage into or through

The validation of a proposition by application of specified rules, as of induction or deduction, to assumptions, axioms, and sequentially derived conclusions, The presentation of sufficient evidence_ as, the burden of proof lies with the plaintiff, The state of having been tested and approved; firmness, hardness, or impenetrability_ specifically applied to arms or armor of defense, to note that they have been duly tested and are impenetrable, intransitive verb_ To work (dough) into proper lightness, To make a trial impression of (printed or engraved matter), To become properly light for cooking, adjective_ Used to proofread or correct typeset copy, Of standard alcoholic strength, Fully or successfully resistant; impervious. Often used in combination

Land covered with a dense growth of tropical vegetation, A dense thicket or growth, A dense, confused mass; a jumble, A dense growth of rank and tangled vegetation, large and small, often nearly impenetrable, such as is characteristic of some parts of India, especially in the swampy regions at the base of the Himalaya mountains