IPA: /ˌʌnɪnˈtɛlɪdʒəntli/
KK: /ʌnɪnˈtɛlɪdʒəntli/
In a way that shows a lack of understanding or intelligence.
He spoke unintelligently about the complex topic, making it hard for others to follow.
Unintelligently → It is formed from "un-" (meaning not), "intelligent" (from Latin "intelligentem", meaning understanding or discerning), and "-ly" (meaning in a manner). The word "unintelligently" means in a manner that is not understanding or discerning.
Think of 'not' ('un-') being added to 'understanding' ('intelligent') to remember that 'unintelligently' means acting in a way that lacks understanding.