Insidious

/ɪnˈsɪdi.əs/ · adjective

Meaning

Causing harm in a stealthy, often gradual, manner..

Definitions by Sense

1. Causing harm in a stealthy, often gradual, manner.
2. Intending to entrap; alluring but harmful.
3. (nonstandard) Treacherous.

Example Sentences

Strong and vigorous man as he looks, Livingstone has been for years the victim of a secret and insidious disease.

At some point in time they may become the source of an insidious cancer.

The nurse always must be alert to signs of slow leak or insidious infiltration.

The impact on rural communities of rail closures was acute, but I would argue that the worst outcome it created was the long-term diminishment of suburban capacity outside London, which has had a far more insidious effect on rail usage nationally.

Hansel and Gretel were lured by the witch’s insidious gingerbread house.

All these facts clearly appear to me now to establish that the sanctioned scheme was a part of a bigger and […] more insidious scheme which was to hoodwink the creditors and to firmly establish and consolidate the position […]

This seemed to her the worst defilement into which this insidious city had cheated her and in her agitation, she nearly ran into the latrine, […]

Gashford slid his cold insidious palm into his master's grasp, and so, hand in hand, and followed still by Barnaby and by his mother too, they mingled with the concourse.

Synonyms for insidious

Antonyms for insidious

Related Words

Word Forms

• more insidious
• most insidious

Usage Notes

Choose a synonym only when it preserves the intended meaning, tone, and grammar of the full sentence.

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