Words / C1

in-SID-ee-uh-s/ɪnˈsɪdiəs/

Insidious means spreading gradually in a harmful way that is hard to notice: an insidious leak, insidious bias. Gradual (already in the dictionary) is pace without the harm; stealthy is a cousin. A silent drop of the night cohort is still a methods choice.

Meaning

Spreading gradually in a harmful way that is hard to notice.

Examples

• “An insidious drop of the night cohort from the n is still a methods choice.”
• “Stealthy is the close twin. Subtle is milder. A drop is a decision. A limitations line is methods. Name the exclusion, or put the nights back.”

Good to know

Harmful in a gradual, hidden way. Close: stealthy. A silent drop ≠ an unnamed choice.

Near in meaning

stealthy, subtle, creeping

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