'amphigastrium' originates from Greek, specifically the word 'amphi' meaning 'on both sides' and 'gaster' meaning 'stomach'.

'amphi' and 'gaster' combined in Greek to form 'amphigastrion', which eventually became the modern English word 'amphigastrium'.

Initially, it referred to the area around the stomach, but over time it evolved to specifically denote the lower abdomen in certain invertebrates.