'pigsty' originates from Old English, specifically the word 'stī', where 'stī' meant 'enclosure or pen'.

'stī' transformed into the Middle English word 'sty', and eventually became the modern English word 'pigsty' by combining with 'pig'.

Initially, it meant 'an enclosure for pigs', but over time it evolved to also mean 'a very dirty or untidy place'.