IPA: /ˈrædɪkli/
KK: /ˈrædɪkli/
In a way that is very different from the usual or traditional; fundamentally or extremely.
The new policy will radically change how we approach education.
Radically → It is formed from "radix" (meaning root) and the suffix "-ally" (meaning in a manner relating to). The word "radically" means in a manner that relates to the root or fundamental nature of something.
Think of 'root' ('radix') to remember that 'radically' means relating to the fundamental nature of something.