It depends on what the sentence is: The brightness of the sun is blinding. The word brightness would be an adjective.
I will help adjust the brightness of your TV screen.
Brightness is a noun, the condition of being bright
brilliance; brightness
An apparent brightness is the brightness of a star as measured by an observer.
I can give you a sentence using the word galaxy.
he fends off the brightness of sun with shade.
The brightness of the tele was too great to look at.
I will help adjust the brightness of your TV screen.
Brightness is a noun, the condition of being bright
luminosity is synonymous to brightness
The word bright has one syllable. It is pronounced BRYT.
Correct, your Brightness! The brightness of the polished brass conflicted with the dark tones of the English oak paneling.
brightness
huliumous
gowtham- a mean of brightness
This word if often used in describing the brightness of a colour. test it out in a conversation with a freind. eg. These are very annal socks or the stars were very annal tonight or Your dress is very annal.
Your cleverness in deciding to use steel wool resulted in the magnificent brightness of the chrome bumper that we see before us.