Insidious meaning in English

Learn how to use Insidious correctly with Gymglish.
Test and improve your English. Start your free trial today.

TEST YOUR ENGLISH Free trial and no commitment to buy
4,6 on App Store, Play Store and Trustpilot
More than 7 million learners worldwide

Definition

insidious: cunning, deceitful, devious, treacherous adjective
insidiously (developed): astutely, craftily, cunningly, slyly (developed) adverb
  • "The rest is an insidious attempt to ruin my reputation."

Still unsure of the best way to use 'Insidious'? Improve your English thanks to our online English lessons. We offer a free test as well as a free level assessment!

What our users say:

Pleasure

         

I enjoy doing my online English lessons. Only ten minutes daily are enough...Thank you!

Innovative

         

I love your innovative method which allows me to learn a new language and have fun at the same time!

Unique

         

Your method is unique! Your courses have helped me to progress and gain confidence during my travels.

Progress

         

Gymglish has allowed me to improve my English. A daily routine I wouldn't miss for anything in the world!

More testimonials.

Test your English with Gymglish today and get a free level assessment

Absolutely free - no strings attached.

TEST YOUR ENGLISH