IPA: /ˈruːdli/
KK: /ˈrudli/
In a way that shows a lack of respect or politeness.
He spoke rudely to the waiter, which made everyone uncomfortable.
Rudely → It is formed from "rude" (from Latin *rudis*, meaning unrefined or rough) and "-ly" (a suffix used to form adverbs). The word "rudely" means in a manner that is unrefined or lacking in manners.
Think of 'rude' as being unrefined or rough, and remember that 'rudely' means behaving in an unrefined manner.