It seems to me more natural to use a plural name for a collection, and a singular name for an instance. There isn't a fundamental difference between a sql/mongo

It seems to me more natural to use a plural name for a collection, and a singular name for an instance. There isn't a fundamental difference between a sql/mongo table and a list/array in this sense. Occasionally you'll have a collection of collections so you have to give it a double-plural name like "hobitses", but I have it on good authority that that is totally a legit word.