IPA: /ˈræθfəli/
KK: /ˈræθfəli/
In a manner that shows strong anger or rage.
She spoke wrathfully after hearing the unfair decision.
Wrathfully → It is formed from "wrath" (from Old English "wræth", meaning intense anger) and "-fully" (meaning in a manner full of). The word "wrathfully" means in a manner full of wrath or anger.
Think of someone acting 'full of anger' — 'wrath' means intense anger, and '-fully' indicates the manner of that anger.