Source : Webster's Revised Unabridged Dictionary (1913)

Studious \Stu"di*ous\, a. [L. studious: cf. F. studieux. See
   {Study}.]
   1. Given to study; devoted to the acquisition of knowledge
      from books; as, a studious scholar.

   2. Given to thought, or to the examination of subjects by
      contemplation; contemplative. --Locke.

   3. Earnest in endeavors; aiming sedulously; attentive;
      observant; diligent; -- usually followed by an infinitive
      or by of; as, be studious to please; studious to find new
      friends and allies.

            You that are so studious Of my affairs, wholly
            neglect your own.                     --Massinger.

   4. Planned with study; deliberate; studied.

            For the frigid villainy of studious lewdness, . . .
            with apology can be invented?         --Rambler.

   5. Favorable to study; suitable for thought and
      contemplation; as, the studious shade. [Poetic]

            But let my due feet never fail To walk the studious
            cloister's pale.                      --Milton.
      -- {Stu"di*ous*ly}, adv. -- {Stu"di*ous*ness}, n.

Source : WordNet®

studiousness
     n : diligent study