IPA: /ˌʌnəˈpiːlɪŋ/
KK: /ʌnəˈpilɪŋ/
Not attractive or pleasing in appearance or quality.
The restaurant's decor was unappealing, making it hard to enjoy the meal.
Unappealing → It is formed from "un-" (meaning not) and "appealing" (from Latin "appellare", meaning to call or appeal). The word "unappealing" means not appealing or lacking attractiveness.
Think of 'not' ('un-') being added to 'appealing' — this helps you remember that unappealing means something that is not attractive.