Definition of musters:
(n) :
(military) An assembling or review of troops, as for parade, verification of numbers, inspection, exercise, or introduction into service.
(n) :
A gathering.
(n) :
An assemblage or display; a gathering, collection of people or things.
(v) :
(transitive) To collect, call or assemble together, such as troops or a group for inspection, orders, display etc.
(v) :
(intransitive) To be gathered together for parade, inspection, exercise, or the like (especially of a military force); to come together as parts of a force or body.
(n) :
(Australia, New Zealand) A roundup of livestock for inspection, branding, drenching, shearing etc.