Merriam-Webster's Collegiate® Dictionary, 11th Edition
INFLUENCE
I. noun see: fluid
Date: 14th century
1. an ethereal fluid held to flow from the stars and to affect the actions of humans, an emanation of occult power held to derive from stars, an emanation of spiritual or moral force,
3. the act or power of producing an effect without apparent exertion of force or direct exercise of command, corrupt interference with authority for personal gain, the power or capacity of causing an effect in indirect or intangible ways ; sway , one that exerts influence, Synonyms: see: influence
II. transitive verb (-enced; -encing)
Date: 1658
to affect or alter by indirect or intangible means ; sway , to have an effect on the condition or development of ; modify , see: affect influenceable adjective