Word of the Day : December 7, 2014


adjective im-PER-vee-us


1 a : not allowing entrance or passage : impenetrable

b : not capable of being damaged or harmed

2 : not capable of being affected or disturbed

Did You Know?

The English language is far from impervious, and, of course, a great many Latinate terms have entered it throughout its history. Impervious is one of the many that broke through in the 17th century. It comes from the Latin impervius, which adds the prefix im- to pervius, meaning "passable" or "penetrable." Pervius-which is also the source of the relatively uncommon English word pervious, meaning "accessible" or "permeable"-comes from per-, meaning "through," and via, meaning "way."


Jane remains impervious to any attempt to reason with her; she’s made up her mind and nothing we can say will lead her to change it.

"Boot trends come and go every fall-over-the-knee, ankle, combat, wedges-but one boot remains, impervious to passing fads: the cowboy boot." - Bethany Ao, The News & Observer (Raleigh, North Carolina), November 5, 2014

Test Your Vocabulary

What word beginning with "h" can mean "impervious to air" or "solitary"? The answer is …


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