IPA: /ˈjuːsləsli/
KK: /ˈjusləsli/
In a way that does not have any value or usefulness.
He tried to fix the old car, but he worked uselessly for hours.
Uselessly → It is formed from "useless" (from the combination of "use" (from Old French *user*, meaning to employ or utilize) and "-less" (meaning without)) and "-ly" (meaning in a manner). The word "uselessly" means in a manner that is without use or purpose.
Think of something that is 'without use' ('useless') and how it is done 'in a manner' ('-ly'). This helps you remember that 'uselessly' describes actions that serve no purpose.