Main entry: pile up, accumulate, amass, cumulate, conglomerate, gather
Definition: collect or gather
Usage: Journals are accumulating in my office; The work keeps piling up
Main entry: stack up, pile up, heap up
Definition: arrange into piles or stacks
Usage: She piled up her books in my living room
Main entry: hoard, roll up, pile up, amass, accumulate, collect, compile
Definition: get or gather together
Usage: I am accumulating evidence for the man's unfaithfulness to his wife; She is amassing a lot of data for her thesis; She rolled up a small fortune