'bristly' originates from Old English, specifically the word 'bristel,' where 'bristle' meant 'a short, stiff hair.'

'bristel' transformed into the Middle English word 'bristil,' and eventually became the modern English word 'bristle,' from which 'bristly' is derived.

Initially, it meant 'a short, stiff hair,' but over time it evolved into its current meaning of 'having a stiff and prickly texture.'