'dairy' originates from Middle English, specifically the word 'deyerye,' where 'dey' meant 'female servant' and '-ery' denoted a place of work.

'deyerye' transformed into the modern English word 'dairy,' and eventually combined with 'containing' to form 'dairy-containing.'

Initially, 'dairy' referred to a place where milk was processed, but over time it evolved to refer to products made from milk.