give currency (to something)
To make something seem more credible or probable, perhaps by providing additional information or details. You're famous in this field—if you comment this guy's wacky notions, you'll just be giving currency to them. Ultimately, we need an expert to give currency to our findings.
give currency (to something)
to spread a story around. (With a negative if there is doubt about what is said.) I can't give any currency to anything Ralph Jones says. We give no currency to those stories. His actions gave currency to the rumor that he was about to leave.