assiduous

Từ điển American Heritage Dictionary 4th

as·sid·u·ous (ə-sĭjʹo͞o-əs)adj.
1. Constant in application or attention; diligent:
an assiduous worker who strove for perfection.
See Synonyms at busy.
2. Unceasing; persistent:
assiduous research. [From Latin assiduus, from assidēre, to attend to : ad-, ad- + sedēre, to sit; See sed- in Indo-European Roots.] as·sidʹu·ous·ly adv.as·sidʹu·ous·ness n.