subprogram
/ˈsʌbprəɡræm/Definitions
1. noun
A program or set of instructions that is part of a larger program or system.
“The company uses a combination of main programs and subprograms to manage their finances.”
2. noun
A smaller program or subroutine used by a larger program or system.
“The computer science student studied the different subprograms used in the operating system.”