IPA: /ˈɜrnɪstli/
KK: /ˈɜrnɪstli/
In a serious and sincere way, showing deep feelings or intentions.
She spoke earnestly about her desire to help others.
Earnestly → It is formed from "earnest" (from Old English *eornost*, meaning serious or grave) and the suffix "-ly" (meaning in a manner of). The word "earnestly" means in a serious or sincere manner.
Think of being serious or sincere ('earnest') and how the '-ly' makes it describe the manner of that seriousness.