IPA: /ˌʌn.ænˈtɪ.pə.teɪ.tɪd/
KK: /ʌnˈæntɪˌpeɪtɪd/
Something that was not expected or predicted to happen.
We faced some unanticipated challenges during the project.
Unanticipated → It is formed from "un-" (meaning not) and "anticipate" (from Latin "anticipare", meaning to take before or foresee). The word "unanticipated" means not foreseen or expected.
Think of 'not' ('un-') being added to 'foreseeing' ('anticipate') — that's why unanticipated means something that was not expected.