IPA: /ˌʌnɪˈmædʒɪnətli/
KK: /ʌnɪˈmædʒɪnətli/
In a way that lacks creativity or imagination; done without original thought.
The project was completed unimaginatively, following the same old methods without any new ideas.
Unimaginatively → It is formed from "un-" (meaning not) and "imaginative" (from Latin "imaginativus", meaning able to form images or ideas). The suffix "-ly" (meaning in a manner) indicates the manner of being. Thus, "unimaginatively" means in a manner that is not imaginative or lacking creativity.
Think of 'not' ('un-') being combined with 'able to form ideas' ('imaginative') — this helps you remember that 'unimaginatively' means lacking creativity.