Definitions

1. noun

an instrument for measuring the intensity of light

“The astronomer used a photometer to calculate the luminosity of the distant star.”

2. noun

a device that measures the light intensity of a photographic image

“The photometer helped the photographer adjust the brightness of the image to achieve the perfect exposure.”

3. verb

to measure the intensity of light

“The researcher photometered the light levels in the room to ensure the optimal conditions for the experiment.”