'creep' originates from Old English, specifically the word 'crēopan', where the root meant 'to creep, to crawl'.

'creep' changed from Old English 'crēopan' to Middle English 'crepen' and eventually became the modern English word 'creep' (with the present-tense form and derived nouns/adjectives developing later).

Initially, it meant 'to crawl or move on hands and knees', but over time it evolved into its current range of meanings including 'move stealthily' and figuratively 'cause unease' or denote an unpleasant person.