'barycenter' originates from New Latin and modern scientific formation, built from the combining form 'bary-' from Greek 'barus' meaning 'heavy' and 'center' from Greek 'kentron' meaning 'center'.

'bary-' (from Greek 'barus') and 'centre' (from Latin and Greek 'kentron') were combined in scientific languages (French, German, English) as 'barycentre' or equivalents in the 19th century; the English variant 'barycenter' (especially in US usage) developed as an English spelling variant of 'barycentre'.

Initially used in technical physics contexts to denote a system's weight-related center or center of gravity, it has come to be used specifically as the 'center of mass' of a system in astronomy and mechanics.