'well-reviewed' is a compound of English 'well' and 'reviewed'. 'Well' comes from Old English 'wel' meaning 'in a good way', and 'reviewed' derives from 'review', ultimately from Anglo-Norman/Old French 'revue' (from verb 'revoir'), from Latin elements meaning 'see again'.

'review' entered English via Anglo-Norman/Old French 'revue' (literally 'a seeing again' from re- + voir/to see) and became Middle English 'review'. 'Reviewed' is the past participle form used in modern English; combined with 'well' it formed the compound adjective 'well-reviewed'.

Individually 'well' meant 'in a good manner' and 'review' originally referred to 'a seeing again' or 'examination'; together the compound evolved to mean 'having been examined and judged favorably', i.e., 'received positive evaluations'.