IPA: /ʌnˈsɛtəlɪŋli/
KK: /ʌnˈsɛtəlɪŋli/
In a way that causes discomfort or anxiety.
The movie was unsettlingly realistic, making the audience feel uneasy.
Unsettlingly → It is formed from "un-" (meaning not), "settle" (from Old French *setler*, meaning to place or establish), and "-ingly" (a suffix used to form adverbs). The word "unsettlingly" means in a manner that does not establish a sense of comfort or stability.
Think of 'not' ('un-') allowing something to be 'established' ('settle') — that's why unsettlingly describes a way that disrupts comfort.