Definition

In a way that is extremely small or tiny, often to the point of being almost unnoticeable.

Example

The changes in temperature were infinitesimally small, barely affecting the overall climate.

Conversation

Did you notice how the temperature dropped today?

Yeah, it feels infinitesimally cooler than yesterday.

I agree, but it’s still pretty warm overall.

True, just a tiny change can make a difference.

Synonyms & Antonyms

Root Explanation

Infinitesimally → It is formed from "in-" (meaning not), "finitus" (meaning finite or limited), and "-esimal" (from Latin *esimus*, meaning very small). The word describes something that is not finite, or in other words, an extremely small quantity that approaches zero.

Memory Tip

Think of something that is 'not finite' ('in-') and 'very small' ('-esimal') — that's why infinitesimally means an extremely tiny amount.

Visually Confused Words