The meaning of collection is the act or process of collecting. how to use collection in a sentence. Synonyms for collection: assemblage, library, accretion, accumulation, cumulation, cumulus, gathering, lodgment. Collection: (accumulation), noun accession , acervation , acervus , acquisition , addition , aggregate , aggregation , amassment , amount accrued , compilation. Find 53 ways to say collection, along with antonyms, related words, and example sentences at thesaurus , the world's most trusted free thesaurus. A collection is a class, so you must declare an instance of the class before you can add elements to that collection. if your collection contains elements of only one data type, you can use one of the classes in the system.collections.generic namespace. a generic collection enforces type safety so that no other data type can be added to it.