'unevenly-reviewed' originates from Modern English, formed by combining the adverb 'unevenly' (from 'uneven' + adverbial suffix '-ly') and 'reviewed', the past participle of 'review'.

'uneven' itself comes from the prefix 'un-' + 'even' (Old English 'efen' meaning 'level'), while 'review' comes from Anglo-French/Old French roots (Old French 'revoire'/'revue' from 're-' + 'voir' meaning 'to see again'), and 'reviewed' is the past participle form that entered Modern English usage; the compound construction (adverb + past participle) is a productive Modern English pattern, producing terms like 'poorly-received' and 'highly-regarded'.

Initially, 'uneven' meant 'not level' and 'review' meant 'to look over or inspect again'; over time the compound came to mean 'having been evaluated in an inconsistent manner' (i.e., 'received mixed reviews').