Today, in science, I learned what the abbreviation, dB means. It means decibel. Decibels can be used as a unit for a label of sound. Just like mi. is for miles, ft. is for feet... Etc. So if something is 85 dB, then it is really loud, but if it is 20 dB, it is really quiet. Also, did you know that anything over 85 dB can be deafening? As in literally.