'homomerous' originates from Greek, specifically the word 'ὁμομερής (homomerēs)', where 'homo-' meant 'same' and 'meros' meant 'part'.

'homomerēs' from Greek was adopted into New Latin/Neo-Latin scientific usage as 'homomerus' and was later borrowed into English as 'homomerous' in scientific contexts (especially zoology and morphology).

Initially, it meant 'having like parts' in Greek and this core meaning has been retained in modern scientific English as 'having similar parts or segments'.