The Collaborative International Dictionary of English v.0.48:

Amiable \A"mi*a*ble\, a. [F. amiable, L. amicabilis friendly,
   fr. amicus friend, fr. amare to love. The meaning has been
   influenced by F. aimable, L. amabilis lovable, fr. amare to
   love. Cf. Amicable, Amorous, Amability.]
   1. Lovable; lovely; pleasing. [Obs. or R.]
      [1913 Webster]

            So amiable a prospect.                --Sir T.
                                                  Herbert.
      [1913 Webster]

   2. Friendly; kindly; sweet; gracious; as, an amiable temper
      or mood; amiable ideas.
      [1913 Webster]

   3. Possessing sweetness of disposition; having sweetness of
      temper, kind-heartedness, etc., which causes one to be
      liked; as, an amiable woman.
      [1913 Webster]

   4. Done out of love. [Obs.]
      [1913 Webster]

            Lay an amiable siege to the honesty of this Ford's
            wife.                                 --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

amiable
    adj 1: disposed to please; "an amiable villain with a cocky
           sidelong grin"- Hal Hinson [syn: amiable, good-
           humored, good-humoured]
    2: diffusing warmth and friendliness; "an affable smile"; "an
       amiable gathering"; "cordial relations"; "a cordial
       greeting"; "a genial host" [syn: affable, amiable,
       cordial, genial]

Moby Thesaurus II by Grady Ward, 1.0:

114 Moby Thesaurus words for "amiable":
   accommodating, affable, affectionate, agreeable, amicable,
   approachable, benevolent, benign, benignant, blissful, bonhomous,
   brotherly, cheerful, civil, clubbable, clubbish, clubby,
   communicative, companionable, companionate, compatible,
   complaisant, compliant, congenial, cordial, courteous, decent,
   desirable, dulcet, easy, easy-natured, en rapport, enjoyable, fair,
   fair and pleasant, favorable, felicific, felicitous, fine,
   fit for society, fond of society, fraternal, friendlike, friendly,
   generous, genial, gentle, good, good-hearted, good-humored,
   good-natured, good-tempered, goodly, gracious, grateful,
   gratifying, gregarious, harmonious, heart-warming, hearty, honeyed,
   hospitable, indulgent, kind, kindly, lenient, liberal, likable,
   mannerly, mellifluous, mellow, mild, neighborlike, neighborly,
   nice, obliging, open, openhearted, overindulgent, overpermissive,
   peaceable, permissive, pleasant, pleasing, pleasurable,
   pleasure-giving, pleasureful, receptive, responsive, rewarding,
   satisfying, simpatico, sisterly, sociable, social, social-minded,
   sweet, sweet-tempered, sympathique, tractable, unhostile, urbane,
   warm, warmhearted, welcome, welcoming, well-affected,
   well-disposed, well-intentioned, well-meaning, well-meant,
   well-natured, winning, winsome