'Arsinoitherium' is a taxonomic name formed from the Greek-derived elements: 'Arsinoe' (the name of an Egyptian royal, used here as a toponymic/commemorative element) plus Greek 'therion' meaning 'beast'.

'Arsinoitherium' was coined in modern scientific nomenclature by combining the proper name 'Arsinoe' with the Greek 'therion' ('beast'), producing the binomial-style genus name used in paleontology; it did not pass through common-word Old/Middle English stages but was created as a Neo-classical scientific name.

The name originally meant 'Arsinoe's beast' (i.e., a beast named after Arsinoe) and has retained that specialized taxonomic sense as the scientific name of the extinct genus.