Definition of “chaplet”

noun

1. an ornamental wreath of flowers, beads, etc, worn on the head
2. a string of beads or something similar
3. Roman Catholic Church 
   1. a string of prayer beads constituting one third of the rosary
   2. the prayers counted on this string
4. a narrow convex moulding in the form of a string of beads; astragal
5. a metal support for the core in a casting mould, esp for the core of a cylindrical pipe