The antonyms for the word "un-grudgingly" are grudgingly, reluctantly, unwillingly, resentfully, and hesitantly. When someone does something un-grudgingly, they are doing it willingly and without hesitation. However, when someone does something grudgingly, they are doing it reluctantly or unwillingly. For example, if someone gives a gift un-grudgingly, they do so with joy and a generous spirit. In contrast, if they give a gift grudgingly, it is likely that they are doing so out of a sense of obligation or with resentment. When using language, it is important to choose the appropriate word that conveys the intended meaning accurately.