In/with calf Definition 1 of 2Pro Tip 1/3Livestock Specific Primarily used for farm animals like cows, not typically for pets or other animals. The farmer mentioned his best cow was in calf again. Pro Tip 2/3Rural Context Most common in rural or farming communities where breeding cattle is usual. At the country fair, several cows in calf were on display. Pro Tip 3/3Technical Term Considered a technical term, used by those familiar with cattle farming. The vet confirmed that two heifers were in calf during her visit.