someone who solicits financial contributions
"The event coordinator asked Sarah to be a fundraiser since she has such strong connections in the local business community."
a social function that is held for the purpose of raising money
"The local church organized a bake sale as a fundraiser to pay for new roof tiles."
An event undertaken to get money by voluntary contributions for a particular activity, such as equipment for extracurricular sports programs, or to defray laboratory costs (salaries) for research of a cure for a particular disease.
"The school organized a bake sale fundraiser specifically to purchase new uniforms for the track team."