IPA: /ˌʌnɪnˈtɛlɪktʃuəl/
KK: /ʌnɪnˈtɛlɪktʃuəl/
Not related to or involving the use of the mind or intellect; lacking in intellectual qualities.
The movie was entertaining but quite unintellectual, focusing more on action than on deep themes.
Unintellectual → It is formed from "un-" (meaning not) and "intellectual" (from Latin "intellectus", meaning understanding or the ability to think). The word "unintellectual" means not possessing or showing intellectual ability or understanding.
Think of 'not' ('un-') having 'understanding' ('intellectus') — that's why unintellectual means lacking intellectual ability.