'marbled-leafed' is a compound of 'marbled' + 'leafed'. 'Marbled' ultimately comes from Latin 'marmor' via Old French 'marbre', meaning 'marble' (i.e., having streaks or veins like marble); 'leafed' is formed from Old English 'leaf' meaning 'leaf'.

'marbled' passed into Middle English through Old French influences from Latin 'marmor'/'marmore' (Old French 'marbre'), evolving into the adjective 'marbled' in modern English; 'leaf' comes from Old English 'lēaf' which evolved into Middle English 'leef' and then modern 'leaf', with the adjectival/compound form 'leafed' formed productively in Modern English to mean 'having leaves of a specified kind'.

Originally 'marbled' referred to the appearance of marble (stone) with veins or streaks; combined with 'leafed' the compound has come to mean 'having leaves with marble-like or variegated patterns'.