IPA: /ʌnˈfɛːərər/
KK: /ʌnˈfɛrər/
Not just or equitable; treating people or groups in a way that is not right or balanced.
The new rules are unfairer to the students who need extra help.
Comparative: more unfair
Superlative: most unfair
Unfairer → It is formed from "un-" (meaning not) and "fair" (from Old English *fæger*, meaning beautiful or just). The suffix "-er" indicates a comparative form. Thus, "unfairer" means more not just or more unjust than something else.
Think of 'not just' ('un-') and 'fair' ('fæger') to remember that 'unfairer' means more unjust.