onerous

adj

1. Imposing or constituting a physical, mental, or figurative load which can be borne only with effort; burdensome.

   “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.”

   “The striker's job was onerous, too, because there was so little "give" in the metal, and the perpetual jarring was indeed trying to the muscles.”

   “However, given current sensibilities about individual privacy and data protection, the recording of oral data is becoming increasingly onerous for researchers[.]”