IPA: /ˈluːsli/
KK: /ˈlusli/
In a way that is not tight or firmly held; in a relaxed or free manner.
The rope was tied loosely, allowing for some movement.
Loosely → It is formed from "loose" (from Old English *losian*, meaning to lose or set free) and "-ly" (meaning in a manner of). The word "loosely" means in a manner that is free or not tight.
Think of something that is 'set free' ('loose') and done 'in a manner' ('-ly') — that's why loosely means done in a free or relaxed way.