The correct spelling of the word pronounced "un interests" is "uninterested" (/ˌʌnɪnˈtɛrɪstɪd/). It is a combination of the prefix "un-" (meaning not) and the adjective "interested" (meaning having or showing curiosity or concern). The vowel sound in the second syllable is pronounced as "ih" like in "bit" and the stress is placed on the second syllable. "Uninterested" is commonly used to describe someone who is not interested in a particular thing or topic.