'antepatriarchal' is formed from the Latin prefix 'ante-' meaning 'before' and the adjective 'patriarchal' (from 'patriarch'), where 'patriarch' comes ultimately from Greek 'patriárkhēs' meaning 'chief of a family' (from 'patr-' meaning 'father' + 'arkhēs' meaning 'ruler').

'ante-' originates from Latin 'ante' ('before'); 'patriarchal' comes via Latin and Old French from Greek 'patriárkhēs'. Over time the combining of Latin 'ante-' with the English adjective 'patriarchal' produced the modern compound 'antepatriarchal' to indicate a temporal or developmental position 'before patriarchy.'

Initially the elements meant 'before' (ante-) and 'father-ruler' (patriarch); combined in modern English they describe a condition or quality 'existing before or prior to patriarchal systems,' a relatively recent scholarly/analytic formation rather than a long-established single lexical item.