- (countable) An accumulation of something, is a number or amount of it that has come together over time.
- The failure to pump leads to an accumulation of blood in the heart.
- There was an accumulation of dirt on the part of the floor people were walking on.
- (uncountable) Accumulation is the process of bringing things together.
- The process of salt accumulation in the soil speeds up under poor watering conditions.
- Private investment helped to boost capital accumulation.