Adjective

That all this might not be too onerous on the purses of his rustic patrons, who are apt to consider the costs of schooling a grievous burden, and schoolmasters as mere drones, he had various ways of rendering himself both useful and agreeable.

Again, and more intensely than ever, she desired a fixed occupation,—no matter how onerous , how irksome.

[I]t has become an onerous duty, a wearisome and distasteful task.