'cartoonish' originates from English, specifically the word 'cartoon', where the root 'cartoon' comes from Italian 'cartone' meaning 'large paper' or 'cardboard' and the suffix '-ish' comes from Old English/Germanic '-isc' meaning 'having the quality of'.

'cartoon' changed from the Italian word 'cartone' (originally 'large paper' or 'cardboard' used for preparatory drawings), passed into French as 'carton' and later into English as 'cartoon'; the adjective 'cartoonish' was formed in English by adding the suffix '-ish' to 'cartoon'.

Initially, 'cartoon' referred to a preparatory drawing on paper; over time it came to mean a humorous or satirical drawing and then an image or style characterized by simplification and exaggeration; 'cartoonish' developed to describe things resembling that style, often extending to mean 'overly exaggerated' or 'unrealistic'.