'minx' originates from English, first attested in the late 16th century; its exact source is uncertain but it may be related to Middle English or dialectal forms implying smallness or petiteness (compare Middle English 'minikin'/'minikin' meaning 'little').

'minx' appears in earlier spellings such as 'mynx' or 'minike' in early modern English and gradually standardized to the modern form 'minx'.

Initially associated with smallness or pet-name senses (from forms meaning 'little'), it shifted by the 17th century to denote a pert, saucy, or flirtatious girl and later broadened to a playful or mischievous person.