Return to the home page.

Expand/collapse menu.

Visit Our Sites

Unabridged Dictionary

Learner's Dictionary

Word Central for Kids

Collegiate Dictionary

Expand/collapse menu.

Premium Services

Unabridged Dictionary

Collegiate Dictionary

Encyclopedia Britannica

Institutional Subscriptions

Expand/collapse menu.

Expand/collapse menu.

Word of the Day

Subscriber Help

Expand/collapse menu.

More Word Games

Daily Crosswords

Expand/collapse menu.

Open Dictionary

Alphabetical Browse

Browse Categories

Submit an Entry

Expand/collapse menu.

Spelling Bee Hive

Hive Headquarters

Spelling Champion

Spelling Reform

Expand/collapse menu.

Word for the Wise

Today's Broadcast

Expand/collapse menu.

Books and CD-Roms

Online Services

Palm and Pocket PC

Expand/collapse menu.

Looking Up a Word

Citing the Dictionary

Audio Pronunciations

Word Games Help

Expand/collapse menu.

Merriam-Webster FAQ

Advertising Info

Copyright Notice

Also Visit:
Unabridged
Visual

ESL:
Learner's
for Kids:
Word Central
Spell It!

insidious

Browse the Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

insidious

Main Entry:: in·sid·i·ous
Pronunciation:: \in-ˈsi-dē-əs\
Function:: adjective
Etymology:: Latin insidiosus, from insidiae ambush, from insidēre to sit in, sit on, from in- + sedēre to sit — more at sit
Date:: 1545

1 a: awaiting a chance to entrap : treacherous b: harmful but enticing : seductive <insidious drugs>2 a: having a gradual and cumulative effect : subtle <the insidious pressures of modern life> bof a disease : developing so gradually as to be well established before becoming apparent

— in·sid·i·ous·ly adverb

— in·sid·i·ous·ness noun

Learn more about "insidious" and related topics at Britannica.com

See a map of "insidious" in the Visual Thesaurus

Find Jobs in Your City

Pronunciation Symbols