'double-petaled' originates from English, specifically the words 'double' and 'petal'; 'double' ultimately comes from Latin 'duplus' meaning 'twofold', and 'petal' comes from Greek 'petalon' meaning 'leaf' (via later French).

'double' entered English via Old French 'double' from Latin 'duplus', and 'petal' was borrowed into English in the 18th century from French 'pétale', which comes from Greek 'petalon'; the compound 'double-petaled' is a modern English formation combining these two elements.

Initially the components meant 'twofold' ('double') and 'leaf-like part' ('petal'); over time the compound came to mean 'having extra layers of petals' referring specifically to flowers with fuller (double) blooms.