to gradually get more and more of something over a period of time.
Synonym - AMASS:
I seem to have accumulated a lot of books; By investing wisely she accumulated a fortune.
SYNONYMS collect gather • accumulate . run something up • amass
These words all mean to get more of something over a period of time, or to increase in quantity over a period of time.
collect to bring things or information together from different people or places; to gradually increase in amount in a place: We’ve been collecting data from various sources; Dirt had collected in the corners of the room. NOTE. People sometimes collect things of a particular type as a hobby: to collect stamps. gather to bring things together that have been spread around; to collect information from different sources: I waited while he gathered up his papers; Detectives have spent months gathering evidence.
COLLECT OR GATHER? Both collect and gather can be used in the same way to talk about bringing together data, information or evidence. When talking about things, gather is used with words like things, belongings or papers when the things are spread around within a short distance. Collect is used for getting examples of something from different people or places that are physically separated.
accumulate (rather formal) to gradually get more and more of something over a period of time; to gradually increase in number or quantity over a period of time : I seem to have accumulated a lot of books; Debts began to accumulate. run something up (rather informal) to allow a bill, debt or loss to reach a large total: She had run up a huge phone bill. NOTE. Run up is nearly always used with bill, debt or loss. amass (rather formal) to collect something in large quantities, especially money, debts or information: He amassed a fortune from silver mining.
PATTERNS AND COLLOCATIONS • to collect/gather/accumulate/amass data/evidence/ information • to accumulate/run up/amass debts • to accumulate/run up losses • to accumulate/amass a fortune • Dirt/dust/debris collects/gathers/accumulates. • to gradually/slowly collect/gather/accumulate/amass something