- Learn English
-
Learn grammar
-
List of words
-
Study your cards
-
Hang On, Man!
-
Audio Books
-
More apps
- Recent searches
-
nouns
-
cyclone
-
trimmer
-
answer
-
adducent
-
grandmother
-
few
-
propenyl alcohol
-
trial and error
-
precisely
- Hide translation
insidiously
insidiously /ɪnˈsɪdiəsli/
adverb
-
(
)
In a harmfully insidious manner
(
perniciously
, insidiously
)
in a harmfully insidious manner
These drugs act insidiously
these drugs act insidiously