IPA: /ˌʌnəˈdrɛst/
KK: /ʌnəˈdrɛst/
Something that has not been discussed or resolved, or something that does not have the necessary address on it.
There are many issues in the report that remain unaddressed.
Unaddressed → It is formed from "un-" (meaning not) and "address" (from Old French *adresser*, meaning to direct or to put in order) and the suffix "-ed" (indicating a past participle). The word "unaddressed" means not directed or not put in order, implying something that has not been dealt with or attended to.
Think of 'not' ('un-') directing or putting something in order ('address') — that's why unaddressed means something that hasn't been dealt with.