Synonyms for Sponsor (same or very similar meaning)
WordNet sense 1 (an advocate who presents a person (as for an award or a degree or an introduction etc.)):
presenter
WordNet sense 2 (someone who supports or champions something):
patron, supporter
WordNet sense 3 (do one's shopping at; do business with; be a customer or client of):
frequent, patronize, shop, patronise, frequent, buy at, shop at
From the ODE community, based on WordNet
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