His successors will face the arduous task of fleshing out the content of this “pivot.”
Few whites believed that blacks had the right stuff to tackle tricky and arduous long-distance flights.
Once the budget has been creatively handled, a director still faces the arduous task of casting.
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.