1de·crease 
/dɪˈkri:s/ verb
de·creas·es; de·creased; de·creas·ing /dɪˈkri:s/ verb 1 [no obj] : to become smaller in size, amount, number, etc.
▪ Sales decreased by five percent this year. ▪ The population is decreasing steadily. = The population is steadily decreasing in size. 2 [+ obj] : to make (something) smaller in size, amount, number, etc.
▪ By exercising often, you can decrease [=reduce, lower] your chance of developing heart disease. ▪ The driver decreased her speed as she approached the curve. ▪ These changes will decrease our expenses. — opposite increase
▪ Sales decreased by five percent this year. ▪ The population is decreasing steadily. = The population is steadily decreasing in size.
▪ By exercising often, you can decrease [=reduce, lower] your chance of developing heart disease. ▪ The driver decreased her speed as she approached the curve. ▪ These changes will decrease our expenses. — opposite increase
— decreased adjective
▪ The patient has a decreased appetite. ▪ a decreased risk of heart disease
▪ The patient has a decreased appetite. ▪ a decreased risk of heart disease
— decreasingly adverb
▪ The medication has been decreasingly effective. [=has gradually been becoming less effective]
▪ The medication has been decreasingly effective. [=has gradually been becoming less effective]
