Arduousness

requiring great exertion; laborious; difficult:
an arduous undertaking.
requiring or using much energy and vigor; strenuous:
making an arduous effort.
hard to climb; steep:
an arduous path up the hill.
hard to endure; full of hardships; severe:
an arduous winter.
historical examples

they vary in arduousness: all would be marked “heavy work” in a job specification.
steel charles rumford walker

they scarcely shrink from any business on account of its magnitude, its arduousness, or its hazard.
thoughts on missions sheldon dibble

they know the arduousness of life, which is a lesson we must all learn sooner or later.
the half-hearted john buchan

though not comparing with the arduousness of field service, our duties were by no means slight.
reminiscences of two years with the colored troops joshua m. addeman

no one has rightly entered on the office without being deeply impressed by its greatness, arduousness, and responsibility.
life and work in benares and k-maon, 1839-1877 james kennedy

the task of the charming l-ss was delightful in its simplicity, but fearful in its arduousness.
the harbor of doubt frank williams

this is done by making the hours of labor in different trades to differ according to their arduousness.
looking backward edward bellamy

i am no mr. stanley; and the length, the difficulties, the arduousness of the labour appalled me.
essays in little andrew lang

adjective
requiring great physical or mental effort; difficult to accomplish; strenuous
hard to endure; harsh: arduous conditions
hard to overcome or surmount; steep or difficult: an arduous track
adj.

1530s, “hard to accomplish, difficult to do,” from latin arduus “high, steep,” also figuratively, “difficult,” from pie root -eredh- “to grow, high” (see ortho-). literal sense of “high, steep, difficult to climb,” attested in english from 1709.