Definition

In a way that is gradual and subtle, but with harmful effects.

Example

The disease spread insidiously, showing no symptoms at first.

Conversation

I read an article about how social media can affect mental health.

Yeah, it's pretty concerning how it can impact us.

The way they described it was insidiously creeping into our daily lives.

Absolutely, it's scary how we don't even notice it happening.

Synonyms & Antonyms

Root Explanation

Insidiously is formed from "insidiae" (meaning ambush or plot) and the adverbial suffix "-ously" (meaning in a manner of). The word describes actions that are done in a sneaky or treacherous manner, often with harmful intent.

Memory Tip

Think of 'insidiae' as a plot or ambush, which helps you remember that 'insidiously' means acting in a sneaky or harmful way.

Visually Confused Words