sedulous

Từ điển American Heritage Dictionary 4th

sed·u·lous (sĕjʹə-ləs)adj.
Persevering and constant in effort or application; assiduous. See Synonyms at busy. [From Latin sēdulus, from sēdulō, zealously : sē, without; See s(w)e- in Indo-European Roots + dolō, ablative of dolus, trickery (probably from Greek dolos, cunning. See del-² in Indo-European Roots).] sedʹu·lous·ly adv.sed'u·lous·ness or se·duʹli·ty (sĭ-do͞oʹlĭ-tē, -dyo͞oʹ-) n.