onerous

Etymology

From Middle English onerous, from Middle French onereux, from Old French onereus, from Latin onerosus (“burdensome”), from onus (“load”).

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. 1820, Washington Irving, The Legend of Sleepy Hollow
   [I]t has become an onerous duty, a wearisome and distasteful task. 1910, Jack London, “The Golden Poppy”, in Revolution and Other Essays
   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. 1945 January and February, A Former Pupil, “Some Memories of Crewe Works—III”, in Railway Magazine, page 13
   However, given current sensibilities about individual privacy and data protection, the recording of oral data is becoming increasingly onerous for researchers[.] 2019, Li Huang, James Lambert, “Another Arrow for the Quiver: A New Methodology for Multilingual Researchers”, in Journal of Multilingual and Multicultural Development, →DOI, page 11