IPA: /ˈpeɪtəntli/
KK: /ˈpeɪtntli/
In a way that is clear and obvious to everyone; without any doubt.
The company's patently false claims were quickly debunked by experts.
Patently → It is formed from "patent" (from Latin *patens*, meaning open or evident) and the suffix "-ly" (meaning in a manner of). The word "patently" means in an open or evident manner, clearly visible or obvious.
Think of something being 'open' or 'evident' — that's what 'patently' means, to show something clearly.