Definition

Able to spread disease or infection to others; something that can be easily passed from one person to another.

Example

The doctor warned that the flu is highly infectious this season.

Conversation

Have you heard her laugh? It's so infectious!

I know, right? It always makes me smile.

I wish I had that kind of energy.

You totally do! Just let it out and be yourself.

Synonyms & Antonyms

Root Explanation

Infectious → It is formed from "in-" (meaning into) and "facere" (meaning to make or do). The word "infectious" describes something that makes its way into a host, typically referring to diseases that can spread from one person to another.

Memory Tip

Think of something that 'makes its way into' ('in-') a body, like a disease — that's why we call it infectious.

Visually Confused Words