The Collaborative International Dictionary of English v.0.48:

Study \Stud"y\, n.; pl. Studies. [OE. studie, L. studium, akin
   to studere to study; possibly akin to Gr. ? haste, zeal, ? to
   hasten; cf. OF. estudie, estude, F. ['e]tude. Cf. Etude,
   Student, Studio, Study, v. i.]
   1. A setting of the mind or thoughts upon a subject; hence,
      application of mind to books, arts, or science, or to any
      subject, for the purpose of acquiring knowledge.
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            Hammond . . . spent thirteen hours of the day in
            study.                                --Bp. Fell.
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            Study gives strength to the mind; conversation,
            grace.                                --Sir W.
                                                  Temple.
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   2. Mental occupation; absorbed or thoughtful attention;
      meditation; contemplation.
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            Just men they seemed, and all their study bent
            To worship God aright, and know his works. --Milton.
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   3. Any particular branch of learning that is studied; any
      object of attentive consideration.
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            The Holy Scriptures, especially the New Testament,
            are her daily study.                  --Law.
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            The proper study of mankind is man.   --Pope.
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   4. A building or apartment devoted to study or to literary
      work. "His cheery little study." --Hawthorne.
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   5. (Fine Arts) A representation or rendering of any object or
      scene intended, not for exhibition as an original work of
      art, but for the information, instruction, or assistance
      of the maker; as, a study of heads or of hands for a
      figure picture.
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   6. (Mus.) A piece for special practice. See Etude.
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The Collaborative International Dictionary of English v.0.48:

Study \Stud"y\, v. i. [imp. & p. p. Studied; p. pr. & vb. n.
   Studying.] [OE. studien, OF. estudier, F. ['e]tudier. See
   Study, n.]
   1. To fix the mind closely upon a subject; to dwell upon
      anything in thought; to muse; to ponder. --Chaucer.
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            I found a moral first, and then studied for a fable.
                                                  --Swift.
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   2. To apply the mind to books or learning. --Shak.
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   3. To endeavor diligently; to be zealous. --1 Thes. iv. 11.
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The Collaborative International Dictionary of English v.0.48:

Study \Stud"y\, v. t.
   1. To apply the mind to; to read and examine for the purpose
      of learning and understanding; as, to study law or
      theology; to study languages.
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   2. To consider attentively; to examine closely; as, to study
      the work of nature.
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            Study thyself; what rank or what degree
            The wise Creator has ordained for thee. --Dryden.
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   3. To form or arrange by previous thought; to con over, as in
      committing to memory; as, to study a speech.
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   4. To make an object of study; to aim at sedulously; to
      devote one's thoughts to; as, to study the welfare of
      others; to study variety in composition.
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            For their heart studieth destruction. --Prov. xxiv.
                                                  2.
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WordNet (r) 3.0 (2006):

study
    n 1: a detailed critical inspection [syn: survey, study]
    2: applying the mind to learning and understanding a subject
       (especially by reading); "mastering a second language
       requires a lot of work"; "no schools offer graduate study in
       interior design" [syn: study, work]
    3: a written document describing the findings of some individual
       or group; "this accords with the recent study by Hill and
       Dale" [syn: report, study, written report]
    4: a state of deep mental absorption; "she is in a deep study"
    5: a room used for reading and writing and studying; "he knocked
       lightly on the closed door of the study"
    6: a branch of knowledge; "in what discipline is his
       doctorate?"; "teachers should be well trained in their
       subject"; "anthropology is the study of human beings" [syn:
       discipline, subject, subject area, subject field,
       field, field of study, study, bailiwick]
    7: preliminary drawing for later elaboration; "he made several
       studies before starting to paint" [syn: sketch, study]
    8: attentive consideration and meditation; "after much
       cogitation he rejected the offer" [syn: cogitation,
       study]
    9: someone who memorizes quickly and easily (as the lines for a
       part in a play); "he is a quick study"
    10: a composition intended to develop one aspect of the
        performer's technique; "a study in spiccato bowing"
    v 1: consider in detail and subject to an analysis in order to
         discover essential features or meaning; "analyze a sonnet
         by Shakespeare"; "analyze the evidence in a criminal
         trial"; "analyze your real motives" [syn: analyze,
         analyse, study, examine, canvass, canvas]
    2: be a student; follow a course of study; be enrolled at an
       institute of learning
    3: give careful consideration to; "consider the possibility of
       moving" [syn: study, consider]
    4: be a student of a certain subject; "She is reading for the
       bar exam" [syn: learn, study, read, take]
    5: learn by reading books; "He is studying geology in his room";
       "I have an exam next week; I must hit the books now" [syn:
       study, hit the books]
    6: think intently and at length, as for spiritual purposes; "He
       is meditating in his study" [syn: study, meditate,
       contemplate]