Definition of flocks:
(n) :
A number of birds together in a group, such as those gathered together for the purpose of migration.
(n) :
A large number of animals associated together in a group; commonly used of sheep, but (dated) also used for goats, farmed animals, and a wide variety of animals.
(n) :
A large number of people.
(n) :
Those served by a particular pastor or shepherd.
(n) :
(Christianity) A religious congregation.
(v) :
(intransitive) To congregate in or head towards a place in large numbers.