Relating to or suitable for collecting; characteristic of items gathered as a group or collection.
From Latin 'colligere' (to gather) with English suffix '-ional' (relating to). The adjective form developed alongside the growth of museums and private collecting in the 19th century.
Museums use the term 'collectional value' to mean how much an object is worth because it belongs to a complete collection—sometimes a common item becomes rare and valuable just because it's the missing piece of a set.
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