Impermeable

Adjective

Definition: Not allowing liquids or gases to pass through; not permeable.

Synonyms: Watertight, Waterproof, Impervious

Antonyms: Permeable, Porous, Absorbent

Examples:

The impermeable raincoat kept him dry during the heavy downpour.
The impermeable membrane prevented water from seeping into the basement.

Mnemonics:

"Impermeable" sounds like "im-purr-meable" which can be associated with a waterproof coat that even repels water from a cat's purrs.

Etymology:

Origin:

Derived from the Latin word "impermeabilis" which means "not passable through"

Historical Usage:

The word has been used since the early 19th century to describe the quality of not allowing the passage of substances.

Related Idioms:

Idiom:

"Impermeable barrier"

Explanation:

Refers to a physical or metaphorical barrier that cannot be penetrated or crossed.

Misconceptions:

Misconception:

Confusing "impermeable" with "impermanent" or "impermissible".

Explanation:

While the words may have similar prefixes, their meanings are distinct. "Impermeable" refers to something not allowing liquids or gases to pass through, "impermanent" refers to something temporary or not lasting, and "impermissible" refers to something not allowed or forbidden.