'cat-enthusiast' originates from the English word 'cat' and the Greek word 'enthousiasmos,' where 'enthousiasmos' meant 'inspiration or possession by a god.'

'enthousiasmos' transformed into the English word 'enthusiasm,' and eventually became part of the compound word 'cat-enthusiast.'

Initially, 'enthousiasmos' meant 'inspiration or possession by a god,' but over time it evolved into its current meaning of 'passionate interest.'