IPA: /ˌʌnˈdɪɡnɪteɪd/
KK: /ʌnˈdɪɡneɪtɪd/
Not assigned or specified for a particular purpose or role.
The area was left undesignated for future development.
Undesignated → It is formed from "un-" (meaning not) and "designate" (from Latin "designare", meaning to mark out or appoint). The word "undesignated" means not marked out or not appointed for a specific purpose.
Think of 'not' ('un-') marking something 'out' or 'appointing' it ('designate'). This helps you remember that 'undesignated' refers to something that has not been assigned a specific role or purpose.