impenetrable

word

Definition

Impossible to pass through or enter. It also describes something very hard to understand.

Usage & Nuances

Formal and literary, used for physical barriers ('impenetrable forest') and abstract challenges ('impenetrable argument'). Not used for ordinary obstacles. Common collocations: 'impenetrable wall', 'impenetrable code', 'impenetrable accent'.

Example Sentences

The cave was hidden behind an impenetrable wall of bushes.

basic

We stared at the impenetrable forest, wondering how anyone could get through.

natural

This math problem seems impenetrable to me.

basic

They built an impenetrable fence around the garden.

basic

Her explanation was so dense, it felt totally impenetrable.

natural

Sometimes his handwriting is just impenetrable—I can't read a thing.

natural