IPA: /ˈdʒɔɪfəli/
KK: /ˈdʒɔɪfəli/
In a way that shows great happiness or delight.
She danced joyfully at the celebration.
Joyfully → It is formed from "joy" (from Old French *joie*, meaning happiness or delight) and "-fully" (meaning full of). The word "joyfully" means full of joy or expressing happiness.
Think of feeling 'full of happiness' — 'joy' means happiness, and '-fully' indicates being full of that feeling.