arduous

Từ điển American Heritage Dictionary 4th

ar·du·ous (ärʹjo͞o-əs)adj.
1. Demanding great effort or labor; difficult: “the arduous work of preparing a Dictionary of the English Language” (Thomas Macaulay).
2. Testing severely the powers of endurance; strenuous:
a long, arduous, and exhausting war.
3. Hard to traverse, climb, or surmount. See Synonyms at burdensome. See Synonyms at hard. [From Latin arduus, high, steep.] arʹdu·ous·ly adv.arʹdu·ous·ness n.

• Từ đồng nghĩa / Synonyms:
  straining, strenuous