Heap together is a phrase that can be used when referring to a large collection of items that have been accumulated and piled up in one place. Some synonyms for this phrase include amass, collect, compile, gather, accumulate, stockpile, and conglomerate. These words can be used interchangeably to describe the act of accumulating or bringing together a large quantity of objects or resources. For example, you could say that someone has amassed a collection of books, or that they have compiled a list of useful resources. Other synonyms for heap together might include words like group, cluster, or bundle, which all refer to the idea of bringing together multiple items into a single unit.