[1] : WordNet (r) 2.0

unattractive
     adj 1: lacking beauty or charm; "as unattractive as most mining
            regions" ant: attractive
     2: lacking power to arouse interest; "being unemployed is a
        most unattractive prospect"
     3: not appealing to the senses; "untempting food" syn: untempting
see also:
attractive untempting 

[2] : Moby Thesaurus II by Grady Ward, 1.0

50 moby thesaurus words for "unattractive":
   beautiless, bitter, blemished, blotted, cacophonic, cacophonous,
   defaced, disagreeable, disfigured, dislikable, displeasing,
   distasteful, dysphemistic, dysphemized, homely, inelegant, marred,
   plain, short on looks, sour, spoiled, thankless, uglified, ugly,
   ugly as hell, ugly as sin, unaesthetic, unalluring, unappealing,
   unappetizing, unbeauteous, unbeautiful, uncomely, undelectable,
   undelicious, undesirable, unengaging, unenjoyable, unhandsome,
   uninviting, unlikable, unlovely, unpalatable, unpleasant,
   unpleasing, unpretty, unsavory, unsightly, untasteful, unwelcome

Unattractive >> U Words
Unattractive, definition of term: Unattractive
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