Definitions for rainmaking
Random House Webster's College Dictionary
(among American Indians) a medicine man who by various rituals and incantations seeks to cause rain.
a person who tries to induce rainfall by artificial techniques, as by seeding clouds with silver iodide crystals.
Informal. an executive or lawyer able to secure clients, generate income, etc., as by using political connections.
Origin of rainmaker:
activity intended to produce rain
The attempted artificial production of rain, either by use of magic or by seeding clouds
Hiring someone who creates business opportunities or revenue.