Basic Details
Word: Impenetrable
Part of Speech: Adjective
Meaning: Impossible to get through or into; also, impossible to understand.
Synonyms: impassable, dense, impervious, incomprehensible
Antonyms: penetrable, accessible, clear
How to Spell Impenetrable
Syllables: im - pen - e - tra - ble
Tricky part: The ending is -able, not -ible, and there is an e between the n and the t.
Watch out for: impenetrible, impenatrable, impentrable
Memory tip: If you are able to penetrate something, it is penetrable. Im- says you are not able, so keep the -able: im + penetr + able.
Usage Examples
Example 1: The forest was so thick that it seemed impenetrable even in daylight.
Example 2: The professor's handwriting was neat, but his explanation was impenetrable.
Example 3: Fog lay over the Yamuna Expressway like an impenetrable grey wall.
Fun Fact
The Darien Gap, a stretch of swamp and rainforest between Panama and Colombia, is so dense that the Pan-American Highway has never been built through it.
Practise the CREST Way
Word Cookie
Fill in the missing letters to complete the word:
imp_n_tr_ble
a) e, e, i
b) e, e, a
c) a, e, a
d) e, a, a
Show answer
b) e, e, a. Think of penetrate: two e's, then the a of -able.
Word Connection
Choose the synonym of the word impenetrable as used in the sentence:
The old fort's walls were so thick that the invading army found them impenetrable.
a) unbreakable
b) ancient
c) accessible
d) fragile
Show answer
a) unbreakable. Walls no army can get through are unbreakable; accessible says the exact opposite.
Mingle-Mangle
Unjumble the letters in the sentence to form a meaningful word:
Thick mist made the mountain pass tleparnebmie for three whole days.
a) impermeable
b) impeccable
c) imperishable
d) impenetrable
Show answer
d) impenetrable. Impermeable needs two m's and impeccable two c's; one m, an n and a t fit only impenetrable.
Multiple Choice Questions
1. An impenetrable argument is one that ____.
a) ends very quickly
b) is impossible to follow
c) is about forests
d) is easy to agree with
Show answer
b) is impossible to follow
2. Which of these is most likely to be impenetrable?
a) a paper kite
b) a glass of water
c) a cotton curtain
d) a bank vault door
Show answer
d) a bank vault door
