collection

noun

1. (countable, uncountable)A set of items or amount of material procured, gathered or presented together.

   “The attic contains a remarkable collection of antiques, oddities, and random junk.”

   “The asteroid belt consists of a collection of dust, rubble, and minor planets.”

   “This year's Summer Collection will include a wide range of evening wear.”

   “He has a big collection of stamps.”

   “He has a superb coin collection.”

2. (countable, uncountable)A set of pitch classes used by a composer.

   “The "collectional information" one receives is ambiguous since the collection { C, E, F, G, A } occurs in the key of C and in the key of F.”

   “In fact, students are often taught that specific collections—diatonic, octatonic, and whole-tone, etc.—typify these composers' compositional language.”

   “Simply put, the realm of available collections in a largely diatonic environment is much smaller than it is in truly atonal one.”

3. (countable, uncountable)The activity of collecting.

   “Collection of trash will occur every Thursday.”

4. (countable, uncountable)A set of sets; used because such a thing is in general too large to comply with the formal definition of a set.
5. (countable, uncountable)A gathering of money for charitable or other purposes, as by passing a contribution box for donations.

   “The people here are very good to each other, too. When someone's house burned down, when someone was in the hospital, they took up collections for the people.”

6. (countable, uncountable)Debt collection.
7. (countable, obsolete, uncountable)The act of inferring or concluding from premises or observed facts; also, that which is inferred.

   “We may safely say thus, that wrong collections have been hitherto made out of those words by modern divines.”

8. (UK, countable, uncountable)The jurisdiction of a collector of excise.
9. (countable, plural-normally, uncountable)A set of college exams generally taken at the start of the term.
10. (countable, uncountable)The quality of being collected; calm composure.