Final answer:
The antonym for 'laboriously' is 'effortlessly', indicating an action performed with ease and minimal effort, in contrast to 'laboriously', which implies significant effort.
Step-by-step explanation:
The antonym for the word laboriously is effortlessly. Laboriously is an adverb that describes performing an action in a way that requires significant effort or hard work. On the other hand, effortlessly implies that the action was done smoothly and with ease, requiring little to no effort. For instance, if you say someone completed a task laboriously, you are suggesting it took a lot of work, but if they completed something effortlessly, it seemed easy for them.