'animalise' originates from French, specifically the word 'animaliser', where 'animal' meant 'living being' and the suffix '-iser' meant 'to make'. Ultimately from Latin 'animal' < 'anima' meaning 'breath, soul'.

'animaliser' entered English via scientific and philosophical usage and, through Middle and Modern English development, became the forms 'animalise' (UK) and 'animalize' (US).

Initially, it meant 'to make into an animal or animal substance', and this sense has largely remained in modern usage, extending figuratively to 'to make more animal-like in behavior'.