Definition of in milk in English:
in milk
phrase
(of an animal, especially a cow) producing milk.
‘The data were adjusted for previous lactation milk yield and days in milk at last test day.’- ‘I will refer to goats in milk and to milking goats to reflect the distinction.’
- ‘The champion Friesian heifer in milk saw an honour awarded to Aidan Foody from Ardagh.’
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