The Collaborative International Dictionary of English v.0.48:

Apt \Apt\, v. t. [L. aptare. See Aptate.]
   To fit; to suit; to adapt. [Obs.] " To apt their places."
   --B. Jonson.
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         That our speech be apted to edification. --Jer. Taylor.
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The Collaborative International Dictionary of English v.0.48:

Apt \Apt\ ([a^]pt), a. [F. apte, L. aptus, fr. obsolete apere to
   fasten, to join, to fit, akin to apisci to reach, attain: cf.
   Gr. ? to fasten, Skr. [=a]pta fit, fr. [=a]p to reach
   attain.]
   1. Fit or fitted; suited; suitable; appropriate.
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            They have always apt instruments.     --Burke.
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            A river . . . apt to be forded by a lamb. --Jer.
                                                  Taylor.
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   2. Having an habitual tendency; habitually liable or likely;
      -- used of things.
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            My vines and peaches . . . were apt to have a soot
            or smuttiness upon their leaves and fruit. --Temple.
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            This tree, if unprotected, is apt to be stripped of
            the leaves by a leaf-cutting ant.     --Lubbock.
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   3. Inclined; disposed customarily; given; ready; -- used of
      persons.
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            Apter to give than thou wit be to ask. --Beau. & Fl.
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            That lofty pity with which prosperous folk are apt
            to remember their grandfathers.       --F. Harrison.
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   4. Ready; especially fitted or qualified (to do something);
      quick to learn; prompt; expert; as, a pupil apt to learn;
      an apt scholar. "An apt wit." --Johnson.
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            Live a thousand years,
            I shall not find myself so apt to die. --Shak.
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            I find thee apt . . . Now, Hamlet, hear. --Shak.
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   Syn: Fit; meet; suitable; qualified; inclined; disposed;
        liable; ready; quick; prompt.
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WordNet (r) 3.0 (2006):

apt
    adj 1: (usually followed by `to') naturally disposed toward; "he
           is apt to ignore matters he considers unimportant"; "I am
           not minded to answer any questions" [syn: apt(p),
           disposed(p), given(p), minded(p), tending(p)]
    2: at risk of or subject to experiencing something usually
       unpleasant; "he is apt to lose"; "she is liable to forget"
       [syn: apt(p), liable(p)]
    3: mentally quick and resourceful; "an apt pupil"; "you are a
       clever man...you reason well and your wit is bold"-Bram
       Stoker [syn: apt, clever]
    4: being of striking appropriateness and pertinence; "the
       successful copywriter is a master of apposite and evocative
       verbal images"; "an apt reply" [syn: apposite, apt,
       pertinent]

The Free On-line Dictionary of Computing (19 January 2023):

APT

   1.  Automatically Programmed Tools.

   2.  Audio Processing Technology.