IPA: /ˈdʒɛləsli/
KK: /ˈdʒɛləsli/
In a way that shows envy or resentment towards someone else's success or possessions.
She looked at her friend's new car jealously.
Jealously → It is formed from "jealous" (from Old French *jaloux*, meaning envious or suspicious) and "-ly" (meaning in a manner of). The word "jealously" means in a manner that shows envy or suspicion.
Think of someone acting 'in a manner of' ('-ly') being 'envious' ('jealous') — that's why jealously means to act with envy.