Decrease/dɪˈkriːs/ Definition 1 of 2Pro Tip 1/3Context Matters Use 'decrease' when discussing quantity, size, intensity, or numbers becoming smaller. The volume of the music decreased as she walked away. Pro Tip 2/3Not Always Negative 'Decrease' can be positive, neutral, or negative depending on what is reducing. A decrease in pollution is good for the environment. Pro Tip 3/3Measure Change Often paired with adverbs to indicate the speed or amount of change, like 'significantly'. Her stress levels decreased significantly after vacation.