What does "brightness" mean?

1. (light intensity) the quality of being bright or giving off a lot of light. 2. (intelligence) the quality of being clever or quick to understand things.

brightness

US //ˈbɹaɪtnəs// UK //bɹˈaɪtnəs// bright·ness

1 light intensity (n.)
B1 Intermediate

the quality of being bright or giving off a lot of light.

the state or quality of being bright, referring to the intensity of light emitted or reflected by an object.

Example

You can adjust the brightness of your phone screen in the settings menu.

Example

The sudden brightness of the morning sun reflecting off the fresh snow was almost blinding without sunglasses.
- brilliance
- luminance
- radiance
- darkness
- dimness
- dullness
2 intelligence (n.)
B2 Upper Intermediate

the quality of being clever or quick to understand things.

a figurative extension referring to mental acuity, intelligence, or the ability to grasp concepts quickly.

Example

The teacher was impressed by the brightness of the new student.

Example

Her natural brightness was evident in the way she solved the complex logic puzzles long before her peers had even finished reading the instructions.
- stupidity
- denseness

Origin

From Middle English bryghtnes, brightnesse, from Old English beorhtnes (“brightness, splendor”), from Proto-West Germanic *berhtnassī, equivalent to bright + -ness. Cognate with Old High German berahtnessī, berahtnessi (“brightness”).