'part-covered' is a compound formed from 'part' + past participle 'covered'. 'Part' ultimately comes from Latin 'pars' (via Old French 'part'), where 'pars' meant 'a portion or piece.' 'Cover' comes from Old French 'covrir' (from Latin 'cooperire'), where the prefix 'co-' meant 'together' and 'operire' meant 'to cover'.

The elements 'part' (from Latin 'pars' through Old French) and 'covered' (past participle of 'cover' from Old French 'covrir') were combined in Modern English as a compound adjective to describe something that is covered to some degree but not completely, forming 'part-covered'.

Originally the separate words meant 'a portion' and 'having been covered.' Over time the combined compound came to be used adjectivally to mean 'partially covered' as a single descriptive term.