1 [+ obj] : to make (something) smaller in size, amount, number, etc. : decrease
▪ The medicine reduces the risk of infection. ▪ We are trying to reduce our debt. ▪ Stricter speed limit enforcement has reduced the number of car accidents. ▪ Her prison sentence was reduced from 15 years to 10. ▪ a drastically reduced price 2 [+ obj] a : to cause (someone) to be in a specified state or condition — + to ▪ The movie's ending reduced them to tears. [=made them cry] ▪ The crowd was reduced to silence. [=became suddenly silent]
b : to cause (something) to be in a specified form by breaking it, burning it, etc. — + to ▪ reduce stone to powder ▪ mountains that will someday be reduced to sand ▪ Their house was reduced to ashes [=was completely burned/destroyed] by the fire. ▪ The city was reduced to rubble/ruins by the bombing.
c : to force (someone) to do something that causes shame, embarrassment, etc. — followed by to + -ing verb ▪ The museum has been reduced to begging for funding. 3 [+ obj] : to describe (something) in a way that includes only some of the facts and details — + to ▪ You're reducing religion to a list of do's and don'ts. ▪ Her argument can be reduced to a few essential points. 4 : to boil (a liquid) so that there is less of it [+ obj] ▪ Simmer the broth until it is reduced to 2 cups. [=until there are only two cups of it] [no obj] ▪ Simmer the broth until it reduces to 2 cups. 5 [+ obj] : to change (someone's rank) to a lower or less important one
▪ As part of her sentence, the sergeant's rank was reduced to private. 6 [no obj] US, informal : to gradually decrease your weight by eating less
▪ He's on a (weight) reducing diet. 7 [+ obj] mathematics : to change (a fraction) so that it is written with the lowest possible numbers
▪ You can reduce ²⁄₄ to ¹⁄₂.