A heifer is a young cow. If you work on a farm, you might be tempted to adopt the smallest heifer as your pet, based on cuteness alone.
Heifers are female cows who have not yet given birth to a calf. Farmers can raise heifers for dairy or for meat. In the 1830s, heifer, which is pronounced “HEFF-er,” was first used as slang for “woman” or “girl.” Since then, it took on the meaning of a female who is obese. It is very rude to single people out because of the way they look and so heifer should never be used.