The Collaborative International Dictionary of English v.0.48:

Apply \Ap*ply"\, v. t. [imp. & p. p. Applied; p. pr. & vb. n.
   Applying.] [OF. aplier, F. appliquer, fr. L. applicare to
   join, fix, or attach to; ad + plicare to fold, to twist
   together. See Applicant, Ply.]
   1. To lay or place; to put or adjust (one thing to another);
      -- with to; as, to apply the hand to the breast; to apply
      medicaments to a diseased part of the body.
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            He said, and the sword his throat applied. --Dryden.
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   2. To put to use; to use or employ for a particular purpose,
      or in a particular case; to appropriate; to devote; as, to
      apply money to the payment of a debt.
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   3. To make use of, declare, or pronounce, as suitable,
      fitting, or relative; as, to apply the testimony to the
      case; to apply an epithet to a person.
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            Yet God at last
            To Satan, first in sin, his doom applied. --Milton.
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   4. To fix closely; to engage and employ diligently, or with
      attention; to attach; to incline.
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            Apply thine heart unto instruction.   --Prov. xxiii.
                                                  12.
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   5. To direct or address. [R.]
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            Sacred vows . . . applied to grisly Pluto. --Pope.
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   6. To betake; to address; to refer; -- used reflexively.
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            I applied myself to him for help.     --Johnson.
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   7. To busy; to keep at work; to ply. [Obs.]
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            She was skillful in applying his "humors." --Sir P.
                                                  Sidney.
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   8. To visit. [Obs.]
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            And he applied each place so fast.    --Chapman.
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   Applied chemistry. See under Chemistry.

   Applied mathematics. See under Mathematics.
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The Collaborative International Dictionary of English v.0.48:

Apply \Ap*ply"\, v. i.
   1. To suit; to agree; to have some connection, agreement, or
      analogy; as, this argument applies well to the case.
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   2. To make request; to have recourse with a view to gain
      something; to make application. (to); to solicit; as, to
      apply to a friend for information.
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   3. To ply; to move. [R.]
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            I heard the sound of an oar applying swiftly through
            the water.                            --T. Moore.
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   4. To apply or address one's self; to give application; to
      attend closely (to).
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WordNet (r) 3.0 (2006):

apply
    v 1: put into service; make work or employ for a particular
         purpose or for its inherent or natural purpose; "use your
         head!"; "we only use Spanish at home"; "I can't use this
         tool"; "Apply a magnetic field here"; "This thinking was
         applied to many projects"; "How do you utilize this tool?";
         "I apply this rule to get good results"; "use the plastic
         bags to store the food"; "He doesn't know how to use a
         computer" [syn: use, utilize, utilise, apply,
         employ]
    2: be pertinent or relevant or applicable; "The same laws apply
       to you!"; "This theory holds for all irrational numbers";
       "The same rules go for everyone" [syn: apply, hold, go
       for]
    3: ask (for something); "He applied for a leave of absence";
       "She applied for college"; "apply for a job"
    4: apply to a surface; "She applied paint to the back of the
       house"; "Put on make-up!" [syn: put on, apply]
    5: be applicable to; as to an analysis; "This theory lends
       itself well to our new data" [syn: lend oneself, apply]
       [ant: defy, refuse, resist]
    6: give or convey physically; "She gave him First Aid"; "I gave
       him a punch in the nose" [syn: give, apply]
    7: avail oneself to; "apply a principle"; "practice a religion";
       "use care when going down the stairs"; "use your common
       sense"; "practice non-violent resistance" [syn: practice,
       apply, use]
    8: ensure observance of laws and rules; "Apply the rules to
       everyone"; [syn: enforce, implement, apply] [ant:
       exempt, free, relieve]
    9: refer (a word or name) to a person or thing; "He applied this
       racial slur to me!"
    10: apply oneself to; "Please apply yourself to your homework"