IPA: //ʌnˈsɪstəmaɪzd//
KK: /ʌnˈsɪstəˌmaɪzd/
Not organized or arranged in a systematic way.
The data was unsystematized, making it difficult to analyze.
Unsystematized → It is formed from "un-" (meaning not), "system" (from Greek "systēma", meaning a whole made up of parts), and "-ized" (meaning to make or to become). The word "unsystematized" means not organized into a system or lacking systematic arrangement.
Think of 'not' ('un-') having a 'whole made of parts' ('system') that is 'made' ('-ized') — that's why unsystematized means lacking organization.