impregnable
/ɪmˈpɹɛɡ.nəˌb(ə)l/adj
High School
1
Of a fortress or other fortified place: able to withstand all attacks; impenetrable, inconquerable, unvanquishable.
2
Too strong to be defeated or overcome; invincible.
Thesaurus
Sound Patterns & Rhymes
Alliteration
Words starting with the same consonant sound — used in poetry and prose to create rhythm, emphasis, and memorable phrasing (e.g. “Peter Piper picked”)
Assonance
Words sharing similar vowel sounds regardless of starting letter — creates internal melody in writing