Not attractive or interesting; something that doesn't make you want it or like it.
From un- (not) + appeal (from Latin appellare, to address/attract) + -ing. The prefix 'un-' negates the appeal, originally meaning to call toward something attractive.
The word 'appeal' comes from the same root as 'appall' — both originally meant to address or call to someone, but appeal took a positive turn (attracting you) while appall took a dark turn (calling upon with horror).
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