IPA: /ˈærɪdli/
KK: /ˈærɪdli/
In a way that is dry or lacking in moisture; often used to describe a lack of emotion or enthusiasm.
He spoke aridly, showing no excitement about the project.
Aridly is formed from "arid" (from Latin "aridus", meaning dry) and the suffix "-ly" (meaning in a manner of). The word "aridly" means in a dry manner or lacking moisture.
Think of 'arid' meaning dry, and remember that 'aridly' describes doing something in a dry way.