'morose' originates from Latin, specifically the word 'morosus,' where 'morosus' meant 'peevish or fretful.'

'morosus' transformed into the French word 'morose,' and eventually became the modern English word 'morose' through Middle English.

Initially, it meant 'peevish or fretful,' but over time it evolved into its current meaning of 'sullen and ill-tempered.'