'symmetrical-petaled' originates from English as a compound of 'symmetrical' and 'petaled'. 'symmetrical' ultimately comes from Greek, specifically the word 'symmetria', where 'sym-' meant 'together' and 'metron' meant 'measure'; 'petaled' comes from 'petal' which originates from Greek 'petalon' meaning 'leaf' or 'thin plate'.

'symmetrical' passed into English via Latin and Old French from Greek 'symmetria' and developed into the modern adjective 'symmetrical'; 'petal' entered English in the 19th century from Modern Latin and Greek 'petalon', becoming 'petal' and then taking the adjectival form 'petaled'. The compound 'symmetrical-petaled' is a modern English descriptive formation combining these elements.

Initially, elements meant 'measured together' (from 'symmetria') and 'leaf/thin plate' (from 'petalon'); over time these became specialized so that 'symmetrical' refers to balanced form and 'petal' to a flower's segment, and together they now describe 'petals arranged symmetrically'.