The Collaborative International Dictionary of English v.0.48:

affection \af*fec"tion\ ([a^]f*f[e^]k"sh[u^]n), n. [F.
   affection, L. affectio, fr. afficere. See Affect.]
   1. The act of affecting or acting upon; the state of being
      affected.
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   2. (Philosophy) An attribute, especially a contingent or
      alterable quality or property; a condition; a bodily
      state; as, figure, weight, etc., are affections of bodies.
      "The affections of quantity." --Boyle.
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            And, truly, waking dreams were, more or less,
            An old and strange affection of the house.
                                                  --Tennyson.
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   3. Bent of mind; a feeling or natural impulse or natural
      impulse acting upon and swaying the mind; any emotion; as,
      the benevolent affections, esteem, gratitude, etc.; the
      malevolent affections, hatred, envy, etc.; inclination;
      disposition; propensity; tendency.
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            Affection is applicable to an unpleasant as well as
            a pleasant state of the mind, when impressed by any
            object or quality.                    --Cogan.
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   4. A settled good will; kind feeling; love; zealous or tender
      attachment; -- often in the pl. Formerly followed by to,
      but now more generally by for or towards; as, filial,
      social, or conjugal affections; to have an affection for
      or towards children.
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            All his affections are set on his own country.
                                                  --Macaulay.
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   5. Prejudice; bias. [Obs.] --Bp. Aylmer.
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   6. (Med.) Disease; morbid symptom; malady; as, a pulmonary
      affection. --Dunglison. AS
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   7. The lively representation of any emotion. --Wotton.
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   8. Affectation. [Obs.] "Spruce affection." --Shak.
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   9. Passion; violent emotion. [Obs.]
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            Most wretched man,
            That to affections does the bridle lend. --Spenser.
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   Syn: Attachment; passion; tenderness; fondness; kindness;
        love; liking; good will. See Attachment; Disease.
        [1913 Webster]

WordNet (r) 3.0 (2006):

affection
    n 1: a positive feeling of liking; "he had trouble expressing
         the affection he felt"; "the child won everyone's heart";
         "the warmness of his welcome made us feel right at home"
         [syn: affection, affectionateness, fondness,
         tenderness, heart, warmness, warmheartedness,
         philia]

Moby Thesaurus II by Grady Ward, 1.0:

212 Moby Thesaurus words for "affection":
   Amor, Christian love, Eros, Platonic love, abnormality, access,
   acute disease, admiration, adoration, adore, affect,
   affectionateness, affections, affective faculty, affectivity,
   affliction, agape, ailment, allergic disease, allergy, amativeness,
   amorousness, ardency, ardor, atrophy, attachment, attack,
   attention, attribute, bacterial disease, bent, bias, birth defect,
   blight, bodily love, brotherly love, cardiovascular disease,
   caritas, character, characteristic, charity, chronic disease,
   circulatory disease, complaint, complication, concern, condition,
   congenital defect, conjugal love, crush, defect,
   deficiency disease, deformity, degenerative disease,
   demonstrativeness, derangement, desire, devotion, disability,
   disease, disorder, distemper, disturbance, doting, ecstasy,
   emotion, emotional charge, emotional life, emotional shade,
   emotions, enchantment, endemic, endemic disease, endocrine disease,
   enjoying, epidemic disease, experience, faculty, faithful love,
   fancy, feature, feeling, feeling tone, feelings, fervor,
   finer feelings, flame, fondness, foreboding, free love,
   free-lovism, functional disease, fungus disease,
   gastrointestinal disease, genetic disease, goatishness, goodwill,
   gust, gusto, gut reaction, handicap, heart, heartthrob,
   hereditary disease, hero worship, high regard, horniness,
   iatrogenic disease, idolatry, idolism, idolization, ill, illness,
   impression, indisposition, infatuation, infectious disease,
   infirmity, interest, lasciviousness, leaning, libido, like, likes,
   liking, love, lovelornness, lovemaking, lovesickness, malady,
   malaise, mark, married love, morbidity, morbus, muscular disease,
   neurological disease, nutritional disease, occupational disease,
   organic disease, pandemic disease, paroxysm, passion, passions,
   pathological condition, pathology, penchant, physical love,
   plant disease, popular regard, popularity, predilection,
   presentiment, profound sense, propensity, property,
   protozoan disease, psychosomatic disease, rapture, reaction,
   regard, relish, respiratory disease, response, rockiness,
   romanticism, savor, secondary disease, seediness, sensation, sense,
   sensibilities, sentiment, sentimentality, sentiments, sex,
   sexiness, sexual love, shine, sickishness, sickness, signs, spell,
   spiritual love, susceptibilities, susceptibility, sympathies,
   sympathy, symptomatology, symptomology, symptoms, syndrome, taste,
   tender feeling, tender passion, tender susceptibilities,
   tenderness, the pip, trait, truelove, turn, undercurrent,
   urogenital disease, uxoriousness, virtue, virus disease, warmth,
   wasting disease, weakness, worm disease, worship, yearning



Easton's 1897 Bible Dictionary:

Affection
   feeling or emotion. Mention is made of "vile affections" (Rom.
   1:26) and "inordinate affection" (Col. 3:5). Christians are
   exhorted to set their affections on things above (Col. 3:2).
   There is a distinction between natural and spiritual or gracious
   affections (Ezek. 33:32).


Bouvier's Law Dictionary, Revised 6th Ed (1856):

AFFECTION, contracts. The making over, pawning, or mortgaging a thing to
assure the payment of a sum of money, or the discharge of some other duty or
service. Techn. Diet.