Burdensomely is an adverb that is used to express that something is difficult, tiresome or heavy to bear. Some antonyms for the word burdensomely are lightly, easily, effortlessly, smoothly, and comfortably. Lightly suggests that something is not burdensome or heavy and can be carried with ease. Something that is done easily is not burdensome, and it can be done without much effort or struggle. Smoothly suggests that something can be done without any hiccups or difficulties, and comfortably implies that something can be done without feeling any strain or discomfort. All these antonyms suggest an absence of any heaviness, difficulty, or struggle.