Definition

A device used to measure the strength of radiation, especially sunlight, often used in weather studies.

Example

The scientist used an actinometer to measure the intensity of sunlight during the experiment.

Conversation

Hey, do you know what an actinometer is?

Yeah, I think it's used to measure sunlight or something like that.

Exactly! I read that it's important for meteorology.

That's cool! I never knew there were tools like that for measuring radiation.

Synonyms & Antonyms

Root Explanation

Actinometer → It is formed from "actino-" (from Greek "aktinos", meaning ray) and "-meter" (from Greek "metron", meaning measure). The word refers to an instrument that measures the intensity of radiation, particularly solar radiation, by quantifying the rays.

Memory Tip

Think of 'rays' ('actino-') being 'measured' ('-meter') — that's how an actinometer works to measure light intensity.

Visually Confused Words