IPA: /ˈskɛdʒ.ə.lər/
KK: /ˈskɛdʒʊlər/
A person or device that organizes and manages a timetable or plan for tasks and events.
The scheduler helped us plan our meetings for the week.
Scheduler → It is formed from "schedule" (from Old French *escheduel*, meaning a list or plan) and "-er" (meaning a person who). A scheduler is a person who creates or manages a list or plan of events or tasks.
Think of a person who makes a 'list' or 'plan' ('schedule') for events — that's what a scheduler does.